Fire and Life Safety Inspection Manual [9 ed.] 9781449670825

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Citation preview

Ci.] NFPA®

E:~~!: Fireand LileSafet

ns ec 10n anua RobertE. Solomon,PE Editor NationalFireProtectionAssociation Quincy , Massachusetts

~

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page. 6048 Printed in the United States o f Am erica 16 15 14 13 12 JO 9 8 7 6 5 4 3 2

CONTENTS Preface Acknowledgments Ab out the Auth ors

SECTION 1

vii ix

xi

GENERAL

1

Chapter l

The Fire In sp ecto r David Lind

Chapter 2

Inspecti o n Procedures David Lind

Chapter 3

Hou sekeeping and Building Procedures Jon Nisja

2 7 20

Chapter 4

Rep or t Writing and Record Keeping Ronald R . Farr

34

Chapter 5

Education, Training, Certification, and the Fire Insp ector Larry McDonald

43

Ch apter 6

Sustainable Design and Green Technologies Tracy Golinveaux , MSFPE and Robert E. Solomon , PE

SECTION 2 Ch apt er 7

BUILDING SYSTEMS AND FIRE PROTECTION SYSTEMS

50

69

Building Co nstru ctio n Elements Richard J. Davis, PE, FSFPE

71

Chapter 8

Classific ation of Co nstructi on Types Richard J. Davis , PE, FSFPE

89

Chapte r 9

Co nstructi on, Alteration, and Demolition Operations Richard J. Davis , PE, FSFPE

101

Ch apter 10 Pro tectio n of Openings in Fire Rated Assemb lies Kristin Collette Bigda , PE, MSFPE

112

Chapte r l l Electric al Systems Jea n M. Blanc

129

Chapter 12 Heating Systems Allan B. Fras er

149

Chapter 13 Air-Conditioning

164

and Ventil atin g Syst em s Allan B. Frase r

Cha pt er 14 Smoke -Con trol Systems Michael J. Ferreira, PE, MSFPE

173

Chapter 15 Fire Alarm and Carb on Monoxide Systems Lee Richardson

19 1

Ch apter 16 Water Suppli es Victoria B. Valentine, PE, MSFPE

229

Chapte r 17 Auto mati c Spr inkl er and Other Water -Based Fire Protection Systems Bob Caputo and Roland Huggins

250

Ch apter 18 Water Mist Systems Jack R. Mawhinn ey, PE

270

Chapte r 19 Specia l Agent Ext in guishin g System s Gerald R. Back III

300

Chapt er 20 Clea n Agen t Exting uishin g Systems Tom Wysocki

3 12

Chapt er 2 1 Porta ble Fire Extinguis hers Mark Conroy

323

Ch apt er 22 Means of Egress Ron Cote, PE

337

Ch apte r 23 Interior Finish, Co nt ent s, and Furni shin gs Kri stin Collette Bigda, PE, MSFP E

343

Chapter 24 Comm ission ing Process for Fire Protection Systems Matth e w J. Klaus , MSFPE

35 1

Chap ter 2 5 Accessibility Requirements All a n B. Fraser

366

Chapter 26 Grass, Brus h, and Forest Fire Hazards Michele Steinberg

376

Chapter 27 Road Tunnel s William G. Connell and Matthew J.Klaus, MSFPE

386

Contents SECTION 3

OCCUPANCIES

401

Chapter 28 Assembly Occupancies Josepl, Versteeg Chapter 29 Educational Occupancies Josepl, Versteeg Chapter 30 Daycare FacilitiesJosep/r Versteeg Chapter 3 l Healthcare FacilitiesJoseph M. Jordi11 , PE Chapter 32 Ambulatory Healthcare FacilitiesJoseph M. Jnrdi11,PE Chapter 33 Detention and Correctional Occupancies Josep/rM. Jm-din, PE Chapter 34 Hotels Josep/rM. ]'11rdi11, PE Chapter 35 Apartment Buildings Joseph M. J11rdi11, PE Chapter 36 Lodging or Rooming Houses Josep/rM. Jordi11,PE Chapter 37 Residential Board and Care Occupancies JosephM. Jnrdi11,PE Chapter 38 One- and 'I\1•0-Fami!)' Dwellings Joseph M. Jnrdi11 , PE Chapter 39 Mercantile Occupancies Joseph Versteeg Chapter 40 Business Occupancies Joseph Versteeg Chapter 4 I Industrial Occupancies Joseph Versteeg Chapter 42 Storage Occupancies Joseph Versteeg Chapter 43 Special Structures and High-Rise Buildings Joseph Versteeg

538

SECTION 4

551

Chapter 44 Chapter 45 Clu1pter 46 Chapter 47 Chapter 48 Chapter 49 Chapter 50 Chapter 51 Chapter 52 Chapter 53 Chapter 54 Chapter 55 Clrnpter 56 Chapter 57 Chapter 58 Chapter 59 Chapter 60 Chapter 61

Pholo Credits l11d ex

iv

PROCESS AND STORAGE HAZARDS

Waste-Handling and Processing Systems Sl,nro11S. Gilyeat,PE Radioactive i\faterials Wayne D. Ho/111es , PE, 1\!I SFPE,FSFPE J'vlaterials-Handling Srstcms L, Jeffrey Mnllem General Storage Kristi11Collette Bigda, PE, MSFPE Slornge and Handling of Flammable and Combustible Liquids A11tl,011y M, Ordile, PE Gas Hazards Denise Bench Combustible Dusts G11yColomrn,PE Combustible Metals Ke1•i11Kreilma11 Martha H. C11rlis Hazardous Materials Phillip A. Frida;\ PE Plastics and Rubber Ste11e11E. Yo1111is, PE Explosivesand Blasting Agents Lou D. Sn11tis Fireworks and Prroteclrnics Jol,11R, Steinberg,1'rIDn11dTTrnmnsHandel Heal-Utilization Equipment Ricl111rd A. Gnllng/Jer Spray Painting and Powder Coating Ste1•e11 J, Gr111sel, PE Welding, Cutting, and Other Hot Work 1l11g11st F.Manz nnd De11iseBeac/1 Hazards of Manufactu ring Processes Peter J. Gore Wil/se, PE, FSFPE Aerosol Manufacturing and Storage Midwel J.Madden, PE, FSFPE Protection ofC0111111ercial Cooking Equip111cntR. T. Leicht

""d

402 412 418

422 437 445 458 465

477 485

496 503 509 517 527

553 562

569 586

614 633 645 655 677

692 708 715

73 I 749 771

782 797 814

830 831

Contents

www.Fire.jbpub.com/InspectionManual 111 is text is packaged with a companion website access code that provides free access to inspection forms, which accompany specific chapters in the manual, as listed below. 1l1eseresources will help you remember and record import ant details during your field inspections. Redeem your access code today. Form A-1 Form A-2 Form A-3 Form A-4 Form A-S Form A-6 Form A-7 Form A-8 Form A-9

Form A - IO FormA - 11

FormA - 12 FormA - 13 form A- 14 Form A- IS Forms A-16 and 17 Form A- 18 form A-19

Form A-20 Form A-21

Form A-22 Form A-23

Form A-24 Form A-25 Form A-26 Form A-27 Form A-28

Form A-29 Form A- 30 FormA -31

Form Form Form Form

t\-32 A-33 A-34 A-3S

Ch,1pter 2, lnspec.tion Procedures Chapter 9, Cons truction, Alternlion, and Demolition Operations Chapter 10, Protection of Openi ngs in Fire Rated Assemblies Chapter 11, Electrical Systems Chapter 12, Heating Systems Chapter 13, Air-Conditioning and Ventilating Srstems Chapter Chapter Chapter Chapter

14, Smoke-Control Systems IS, Fire Alarrn Systems 16, Water Supplies 17, Automatic Sprinkler and Other Waler-Based Fire Protection

Systems Chapter 18, Water Mist S)'Stems Chapter 19, Special Agent Extinguishing Systems Chapter 20, Clean Agent Extiugui hing Systems Chapt er 21, Port,1ble Fire Extinguishers Chapter 23, Interior Finish, Contents, and Furnishings Chapte r 24, Commissio ning Process for Fire Protection S}'stcms Chapter 25, Accessibility Requirements Chapter 26, Grass, Brush, ie PolnJs:

6

Cmdil 1.1 lnnovolton m Oo:'.!J gn : Spocd1c T1Uc C1od1t 1.2 ln nov otlon m Do.olgn ; Spocillc Title Ctoot t.:) IMovatlon in Oo.t.lgn; Spoclflc Title Crodit t .-4 lnnovo.tkm1n Oo&1gn: Spcc1llc Title

Croon1.1 5 lnnovnuor,In Oc:;:. ,gn: Spoc1!lc Tl!lo Cmdll 2

lEEO AccrcditOOProlos:-Jonol

MaterJols and Resources

Possible Points:

Regional Prior ity Crodits Regional Priorit y: Cmc:111..!!"Rog.onol Priority ; c,ooH1.~ Rogi on.o.1Pnorl ty : Cfco.Ll . is available on line at www.nfpa.org/70. • 1he National Association of State Fire Marshals maintains a vVeb site with information about fire safety and green buildings for emergency responders and for code officials. TI1eir site can be found at w,vw.greenbuildingfiresafety.org. • UL Environment is a company that tests and verifies the environmental friendliness of products claimed to be green products . UL Environment works directly with product manufacturers and can be contacted at www.ulenvironment.com. • 111e USGBC publishes one of the most popular green building ranking systems: LEED. The USG BC also certifies green buildings according to the LEED point system . Mor e informat ion about LEED and USGBC can be found at www.usgbc.org. • The Solar America Board for Codes and Standards (Solar ABCs) is an organization that provides technical services relating to solar installations and related codes and stand ard s. Inform atio n about Solar ABCs can be found at www.so larabcs.org. • The ASHRAE develops standards and handbooks dealing with HVAC design and en erg}' efficiency. ASH RAE Standard 189.1, Str111dnrd for the Designof HighPe1formnnceGreenBuildings,offers a set of requirements for green building design and can be found at www.ashrae.org/greenstandard. • The National Institute of Building Sciences (NIBS) offers a platform where rep resentatives of government, the professions, industry, labor and consumer inter ests, and regulatory agencies can come together to focus on the identification and resolution of problems and potential problems that hamper the construction of safe, affordable structures for housing, commerce, and industn• throughout the United States. TI1e NIBS High-Performance Building Council has developed a report entitled Assessment to the U.S.Congressnnd U.S.Depnrlment of Energy on High-Pe1formnnceBuildings. TI1is report describes the need to balance sustain able design concepts along with all of the other design features such as usability and environmental, economic, and social impact and can be found at www.nibs . org/index.php/hpbc/. • In Europe, the European Commission publishes a vVeb site with information about sustainable development. TI1e \i\Tebsite can be found at http://ec .europa. eu/ environment/ eussd/. • Fivl Global Group: Approval Standard for Vegetative Roof Systems - Class 4477 (http://www.fmglobal.com/assets/pdf/tinapprovals/4477.pd.)

BlBLIOGRAPHY American Society of Heating, Refrigeration , and Air -Conditioning Engineers (ASHRA E) 62.1 -2007. Geothermal Technologies Program. U.S. Department of Energy. Available at http://wwwl.eere.energy.gov/geothermal/geothermal _basics. html. Accessed November 14, 2011. n.d.

66

CH APT R 6: Sustainable Design ancJGreen Technologies

Glossarr Alternative Fuels & Advanced Vehicles Data Center. U.S.Department ofEnergy. Availableat: http:f/www.afdc.enerm~gov/afrlc/glossary.html.Accessed November 14, 2011. n.d. International Organization for Standardization (ISO) 14021 j. Leitman, S., Build Yo11r011111 P/11g-i11 HybridElectric\leliide, McGraw-Hill,NY,2009,p. 8. Desig11a11d Co11strrictio11. USGBC, U.S. Green l3uilding Council. Green B11ildi11g Washington, DC, 2009. U.S.Environmenta l Protection Agency, 2008. 'v\lind and Water Power Program. U.S. Department of Energy. Available at http:// wwwl.eerc.cnergy.gov/winda ndhydro/ . n.d. http://www.epa.gov/greenbui Iding/pu bs/abou t.hlm. NFPA Codes, Standards, and Recommended Practices

See::the latest version of the NFPA Catalog for availability of current editions of the following documents. NFPA 25, Standard for t/ie /11spectio11, Testing,nnd Mai11te11a11ce of Water-Based Fire Proteclio11 Systems NFPA 70'.E!, National ElectricalCode® NFPA 101®, L!{eSafety Code® NFPA 110, Standardfor E111erge11cy and Standby Power Systems NFPA 5000, Building Co11stmctio11 and Safety Code

67

BUILDING

2 CHAPTER 7

SYSTEMS AND FIRE PROTECTION

SYSTEMS Building Construction Elements Ricl,11rd /. fJai i·, PE, FSFPE 1

CHAPTER8 Classification of Construction Types

Richard/. Davis, PE, FSFPE CHAPTER 9

Construction, AJteration, and Demolition Operations Richard J.Dn11is,PE, FSFPE

CHAPTER 10

Protection of Opening s in Fire Rated Assemb lies Kristin Collette Bigda, PE, MSFPE

CHAPTER 11

Electrical Systems Jea11M. Blanc

CHAPTER 12

Heating Systems Allan B. Fraser

CHAPT ER13

Air-Conditioning and Ventilating Systems Alim, B. Fraser

CHAPTER 14

Smoke -Control Systems lv!ic/l(le/]. Ferreira, PE, J\llSFPE

CHAPTER 15

Fire Alarm and Carbon Monoxide Systems Lee Richardson

CHAPTER 16

Water Supplies Victoria B. Vale11ti11 e, PE, MSFPE

CHAPTER 17

Automatic Sprinkler and Othe1· Water -Based Fire Protection Systems Bob Caputo mid Rola11dHuggins

CHAPTER 18

Water Mist Systems Jack R. Mn111/,i1111 ey, PE

CHAPTER 19

Special Agent Extinguishing Systems Gerald R. Back III

CHAPTER 20

Clean Agent Extinguishing Systems Tom Wy.~ocki

CHAPTER 21

Portable Fire Extingui sher s Mark Conroy

CHAPTER 22

Mean s of Egres s Ron Cote, PE

CHAPTER 23

Interior Finish, Contents , and Furni shing s Kris tin Collette Bigda, PE, MSFPE

CHAPTER 24

Commis sioning Proce ss for Fire Prote ction System s Matthew J.Klaus, MSFPE

CHAPTER 25

Accessibility Requirements Allan B. Fraser

CHAPTER 26

Grass, Brush , and Forest Fire Hazard s Michele Steinberg

CHAPTER 27

Road Tunn els Will iam G. Conne ll and Matthew J.Klaus, MSFPE

CHAPTER

7 \.

BUILDING CONSTRUCTION ELEMENTS Richard J Davis, PE, FSFPE

The type of constructi on and the materials used in a building influence th e building 's life safety and property pro tectio n requirements. In spec tors have a maj or respo nsibil ity in determining th at those requirement s are met through out the life of the building. To dischar ge th at responsibility, the y must kn ow the functi ons of the various structural elem ents of a building (which is th e topic of this chapter) and und ers tand th e significant characteristics of th e various constructi on type s. Because space in this text is limited, inspect ors should refer to th e National Fire Protection Assoc iation (N FPA) Fire Prot ection H andboo k and Frank Brannig an's Building Construction for the Fire Service, both of wh ich cont ain sign ificant additional inform ation.

DEFINITIONS Knowing th e meaning of key term s is essenti al to an und ersta ndin g of h ow the different building con stru ction eleme nt s int era ct. • Bear ing wall: A bearing wall is any wall m eeting eith er of th e following two classifications: (1) any m etal or wood stud wall th at supp ort s m ore th an 100 lb/linear ft (1400 Nim) of vertical loa d in additi on to its own weight or (2) any concre te or m asonry wa ll th at supp orts m ore th an 200 lb/lin ear ft (2900 N/m) of verti cal loa d in additi on to its own weight. • Dead loads: Dead loa ds are loads consisting of th e weight of all materials of constructi on incorporated int o th e building, includin g but n ot limit ed to walls, floors, roofs, ceilin gs, stairw ays, built-in partiti ons, finishes, claddin g, and oth er similarl y incorporated archit ectura l and struc tu ral items, and fixed serv ice equipm ent, includin g th e weight of cranes. • Env ironmental loads: Environmen tal loads are loads caused by the environme nt, includin g wind load, snow load, ice load, rain load, ear thqu ake load, and flood load . • Foundati on syst ems : Found ation syste ms includ e found ation walls, footings, posts, pier s, piles, caissons, or slabs-o n- grade .

SECTION 2: Building Systems and Fire Protection Systems

• Live loads: Live loads are loads, other than dead or environmental loads, produced by the use and occupancy of the building. This includes those loads produced: l. During maintenance, suc h as by workers, maintenance equipment, and materials. 2. During the normal use of the building, such as by other equipment, other contents, and people. • Non bearing wall: A nonbearing wa ll is any wall that is not a bearing wa ll.

FRAMINGMEMBERS In general, the structural components of a building can be divided into two groups: l.

2.

Those elements that support the structure or its framing members. Those that enclose the worki ng, storage, and livin g spaces, that is, its nonbear ing walls, floors, ceilings, and roofs.

The framing m embers form the skeleton of a building, which supports the bui lding and everything attached to it and is part of the dead load. The frame also supports the live load, or the building's contents and its occupants, as we ll as the environmental loads.

Foundation Systems, Columns, and Bearing Walls The structura l frame is supported on foundation systems, which transfer the loads imposed on the building to the ear th below. Co lumns or bearing walls are located on top of these footings and support the floor or floors above a nd th e

FIGURE 7-1Steel anchor bolts are used to secure roof. Steel columns are typically welded steel columns to the footings. to steel bas e plates that are secured to footings using steel anchor bolts (FIGURE 7-1). The failur e of a column or columns from fire exposure is critical because it can resu lt in the collapse of a floor or, in extraordinary cases, of th e entir e building.

Horizontal Structural Members Trusses, beams, girders, joists, and rafters are all typ es of structural members that support a ceilin g, floor, or roof . Live loads and environm ental loads must follow a load path and are typically applied to the cladding or decking. These loads are transferred th ro ugh various roof or floor struct ural members to columns or bearing walls, into foundation systems, and into the earth . 72

CHAPTER 7: Building Construction Elements

Trusses are composed of stee l, wood, comb in ations of steel and wood, or concrete. They include elements of upp er and lower chord members connected to each oth er with vertical and/or diagona l web members to span large distances and to transmit the load directly or indirectly to the building's columns or bearing walls. Beca use of their relatively light weig ht and the type of connect ions, wood trus s members are m ore commonly used in residentia l construcFIGURE 7-2 Solid wood web trusses. tion or in sma ll commercia l projects. Bot h solid web wood trusses and open web wood trusses are particularly vulnerable to fire and, when unprotected (by a fire-res istive coverin g or sprin klers), can collapse after a few minutes of fire exposure (FIGURE 7-2). Open web wood trusses may fail at connection plates, and solid web trusses may fail at the junction of the web and the flanges. This is a common situation in basement areas, which may not be protected by sprinklers or a gyps um board or plaster FIGURE 7-3 Wood beam. ceilin g. If a fire originates in the base ment, unprotected wood trusses supporting the first floor may be ready to collapse at the tim e of initial fire response . Lim ited testing wit h residential spr inkl ers h as been successfu l. A beam is a relatively large horizontal structural member [e.g., 4 by 6 in. to 6 by 10 in. (10 by 15 cm to 15 by 25 cm) ] into which other m embers, suc h as jois ts [e.g., 2 by 8 in. 7-3). or 2 by 10 in. (5 by 20 cm or 5 by 25 cm); wood members], can be framed (FIGURE If a beam is supported on ly at its ends, it usually is called a simp le span beam . If it spans three or more supports, it is a continuous span beam . A girder is a deep beam, such as a stee l beam or glued and laminated (glu-l am) wood beam, into or over which other beams or joists are framed . A joist is one of a series of sma ller, para llel members used directly to support eith er the floor or roof, in which case they are ca lled floor or roof joists, or the ceilin g, where they are called ceiling 7-4). Wood joists joists . Joists genera lly are framed into beams or bearing walls (FIGURE are usually spaced 16 in . (40 cm) on center . A rafter is similar to a joist, except that it supports the roof. Rafters are closely spaced and are usually framed int o beams or bearing walls. For industrial and larg er commercia l construction, stee l framing and concrete con struction are often us ed . For construction such as an insulat ed stee l deck, th e deck is supported by secondary stru ctural framing such as open web steel joists. The depth 73

SECTION 2: Building Syst ems and Fire Protectio n Systems

FIGURE 7-4 Joists.

of th e joists var ies considerab ly, depending primarily on its span but also on the design load and its spaci n g on center. The first number in a stee l joist des ignation is its dept h in inches . For examp le, a 24K6 joist is 24 in. (60 cm) deep. The "K" indicates th at the stee l has a yield stress of 50,000 lb/in.2 (35.2 kg/mm2). The last n umber in this examp le, "6;' is the chord designat ion, which is the relative ranking of the joist's strength. Everyt h ing else being equa l, th e hi gher the FIGURE 7-5 Op en we b steel j oists. chord designation, the stronger the joist. Open web steel joists are supported by primary structura l members, such as wide flange, solid web stee l beams or open web joist girders (FIGURE 7-5) . Steel joists are usu ally spaced 6 ft (1.8 m) or more on center when used to support roofs [2 ft (0.6 m) when supporting concrete mezzanines ] and often span 40 to 50 ft (12.2 to 15.2 m) . Measuring the depth of the joist and its spacing on center is relative ly easy. For new construction, this measurement should be taken and the results checked against the design drawings . For additional information , see the Standard Specifications by the Steel Joist Institute. For wide-flange beams, the "W" indicates that it is a wide flange (FIGURE 7-6). The first number in its designation is the approximate depth in inches; the second number

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CHAPTER 7: Building Construction Elements

is the exact weight in pounds per linear foot. For examp le, a WlO x 49 is 10 in. (25 cm) deep and we ighs exac tly 49 lb/ lin ear ft (73 kg/m). For deeper heavier beams, h owever, the actua l depth may vary considerably from the first number in the designation. Exact dimensions can be fou nd in the American Insti tute of Steel Construction's Steel Design Manual. FIGURE 7-6 Wide-flange beams.

Fire-Protective Coverings Fire-resistance ratings for steel structural fram ing are usually achieved by the application of a spray-applied fire-resistive material. Rated assemb lies are tested in accordance with American Society for Testing and Materia ls (ASTM) E-119 or Underwriters Laborato ries (UL) 263. The actual coating thickness may be adjusted to account for differenc es between the tested steel fram ing member and the actua l steel member in the construction, using formu las noted in the NFPA Fire Protection Handbook . For certain buildings, such as high-rise buildings, the building owner's representative shou ld provide field test data for spray-app lied fire-protective coatings. Two tests that shou ld be used are ASTM E-605 for thickness and density and ASTM E-736 for cohesion and adhesion. Verifying that the thickness of the coating meets the minimum required for the specified fire rating and size of the structural memb er is important and relatively easy. To measure the thickn ess, specia l gauges are available, or a piece of wire or a straightened paper clip can be used and pushed into the coating up to the steel, marked, and then measured after it is taken out (FIGURE 7-7). Measured thickn esses should be checked against listin g req uirements, such as thos e in the UL Fire Resistance Dir ectory, with adjustments made as noted in this chapter . Verifying that the density of the coating meets specified criteria is also important. If th e listed coating is modified from its test ed formulation, it may still meet th e thickness cr iter ia but may not be completely effective because it is too light or lack s

FIGURE 7-7 Gauge to measure thi ckness of fire protect io n coat ing .

75

SECTION 2:

BuildingSystems and Fire Protection Systems

cohes ive strength. Likewise, if the surface is not compatible with the coat ing, the adhesive strength will not be adequate, and the coating may peel off prematurely. It is recommended that an independent laboratory perform these density, adhesion, and cohes ion tests, that it check the results against listing requirements, and that it give the report and the conclusions to the inspector for review. In many cases, it may be practical for the same procedure to be followed for the coating thickness. In some cases, the coat in g thickness needed may be adjusted up or down because the actua l steel member differs in size from the member shown in the listing. This situation is acceptable, provided that the design professional specifies that the assembly will still attain the intended rating; that is, 1 hour, 2 hours, 3 hours, or 4 hours. Typically, structural steel framing is not required to have primer paint prior to the ap plication of spray-applied fire-resistive coatings. The surface should be free of dirt, oil, or loose mill scale. If a primer paint is used, it must be compatib le with the coating. There have been cases in the past where a primer that was not listed for use with the specific fireresistive coating was used, and almost no adhesive strength was provided. If an improper paint is used or the surface is not properly cleaned, the coating may fall off prematurely. Inspectors shou ld be particularly aware of any building renovation/rehabilitation projects that cou ld alter the applied coatings. Coat ings may be in advertent ly removed when ductwork is added or modified, when new communication wiring is added to above-ceiling areas, and even when new pipe for automatic sprinkler systems is insta lled. Any holes in the fire-resistive coatings must be repair ed before the work area is cleared to be occup ied (FIGURE 7-8 and FIGURE 7-9). When stee l deck is used below poured-in-place concrete, it may be used as a composite deck or a noncomposite deck. When used as a composite deck, the stee l deck is int ended to act structura lly with the concrete deck , and so the steel deck must have a fire-resistive covering below it. When used as a noncomposite deck, the steel deck is simply acting as a form deck until the concrete has reach ed its design strength; ther efore, th e stee l deck does not requir e a fire-resistant covering below it. Braces are typically provided perpendicular to purlins, and joists are intended to provide latera l support for th e purlins or joists for snow or wind loads and may not be required to have a fire-resistive coating, even if one is required for the purlins/joists (FIGURE 7·10).

WALLS, FLOOR/CEILING ASSEMBLIES, AND ROOFS Walls Walls serve a variety of functi ons , includin g security, privacy, weather resist ance, fire resistance, and structural resistance. They can be classified as bearing or nonb ea rin g walls, common (or party) walls , shear walls, or fire wa lls or fire barri er walls. Often tim es, a single wall will have two or mor e of th ese functions and may have multipl e classifications.

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CHAPTER 7: Building Construct ion Elements

FIGURE 7-8 Fire resistive material removed from structural member to facilitate sprinkler installation .

FIGURE 7-9 Fire resistive mat erial reinstalled on a structural member following sprink ler installation.

77

SECTION 2: Building Systems and Fire Protect ion Systems

FIGURE 7-10Bracing provid es lateral support for the purlins o r j o ists.

A bearing wall supports more than its own weight, suc h as a floor or roof; a nonbear ing wall typically supports only its own weight. More specifically, a metal or wood stud wa ll that supports more than 100 lb/lin ear ft (1400 N/m) of vertica l load, in add iti on to its own weight, is cons idered a bearing wall. A concrete or masonry wall that supports more than 200 lb/linear ft (2900 N/m), in addition to its own weight, is also considered a b ear ing wall. A common, or party, wall is a single wall that is common to two separate areas or buildings. In some cases, the wood floor joist s of bot h buildings that sh are a common wa ll are placed in the same open ing, providing a hidden pat h for fire to spread . A shear wall acts to brace a portion of a building against the latera l forces of wind, earthquake, or simi lar loads . It resists, by its stiffnes s, th e forces app lied paralle l to its length . Fina lly, a fire wa ll is used to subdivide a building or to separate buildings from each oth er. It has both a fire-resistance rating and structura l stability . Fire walls may be freesta ndin g (cantil evered), doub le walls, or tied wa lls, as defined by NFPA 22 1, Standard for High Challenge Fire Walls, Fire Walls, and Fire Barrier Walls. Wh en a fire wall is used in a single -story bui ldin g or on the top floor of a building, it typica lly pe netrates th e roof and forms a parapet. A fire barri er wa ll is a fire-resistant wall that does not have the structura l stability of a fire wall and is often used to isolate a specia l hazard within a building, suc h as a flam mable liquids storage area. Openings in thes e fire wa lls and fire barrier walls are protected wit h automatic -clos ing or self-closing devices. Fire wa lls usua lly have a fire-resistance rating that ranges from 1 to 4 hours, but their differentiation from fire barrier walls is not with regard to

78

CHAPTER 7: Building Constructio n Element s

fire resistance. Requir ed fire-resistan ce ratings are determined from code requir em ents and are typically based on the occ upancy use . Fire walls should remain structurally sound and sho uld not permit the spread of fire through, und er, over, or around the wall, even if the stru cture on on e sid e of it burns out and collapses. The efficiency of a fire wall depends on its own inte grity and on the reliability of its closing devices . Only certai n types of fire wall design will provide such stability. For more information, the inspector should refer to NFPA 221. Pipe and conduit penetrations shou ld be checked to ensure the piping penetrates the wall at points permitted in the listed assembly. In walls rated for 3 hours and greater, the penetrations must be not more than 3.0 ft (0.9 m) above the floor . Ductwork sho uld be checked to ensure that slip joints are provided near the wall and dampers are provided wi thin the wall. To ens ur e that a true fire wall has been provided, the inspector should check for a parapet, which is a vertical extens ion of the fire wall th at divides the roof and extends at least 30 in. (76.2 cm) above the top surface of th e roof cover. Fire barrier wa lls have fire-resistance ratings ranging from 20 minutes to 4 h ours, but they are usually not structurally ind ependent. Fir e barrier walls rely on the building frame for support, and so their structural integrity is dependent on passive protection of the building frame, automatic spr inkl er protection, or some combination of the two . "Smoke barriers;' which may or may not have a fire-resistance rating, are primarily intended to limit the passage of smoke. Other terms commonly used are "bu ildin g separat ion wa lls;' "area separatio n wa lls;' "fire partitions;' and "occupancy separation walls." Cr it eria for fire barrier walls can be found in NFPA 221. A veneered wall consists of a sing le wythe, or thickness, of brick facing that is later ally supported by wood or steel studs, by concrete, or by masonry. Fire performance is based on the construction of this "backing system:' Fire resistance for concrete and masonry will dep end on the thickness , type of aggregate used, and cover distance for reinforcing steel. For additiona l information on fire resistance, see American Society of Civil Engineers /Socie ty of Fire Protection Engineers (ASCE/SFPE) 29-05. Post -occupancy m od ifications to fire wa lls and fire barri er walls may include instal lation of pipe, wiring, ductwork, or simil ar components that m ay breech the wall and jeopardize its integrity. Insp ector s should verify that any such penetrations have been properly sea led , prov ided with a damper, or otherwise configured to maintain the rat ing that is intended for th e wall. Exterior walls can serve to protect a neighboring building from an exposure fire or 7·11). The amount of fire to prot ect a building from an adjacent expos ur e fire (FIGURE resistance that an exterior wall is required to provide is defined by code and will vary depe nding on the building occupancy . For additiona l informati on , see FM Global Dat a Sheet 1-20. It is important to ensure that no unusual fire exposures deve lop over th e life span of a building that could cause a fire, which is excess ive for the fire rating (or lack of) for the exterior wall, to spread across a separating space. In some cases, th e exter ior wall may be combustib le or its fire int egrity may be limit ed by unprotected openings (FIGURE 7·12). In some cases, th e exterior wall may be loa d-bearing, and, if compromised, collapse of the struct ur e co uld result.

79

SECTION 2: Building Systems and Fire Protect ion Systems

FIGURE 7-11 Exterior walls can protect a neighboring building from an exposure fire or a building from an adjacent exposure fire.

FIGURE 7-12The ext erior wall may be combu stible .

80

CHAPTER 7: Building Construct io n Element s

Often, exterior walls are neither load -bearing nor required to have a fire-r esistance rating. Many industrial buildings have steel framing with metal panel walls . Steel girts are used to latera lly support exterior wa ll panels and lat era lly brace columns (FIGURE7-13). A common type of exterior wall con structi on is the exterior insulati on finish system (EIFS), whic h typically con sists of moisture -resistance gypsum board fasten ed to the exterior side of wall studs, with expanded polystyre ne (XPS) or extrud ed polystyren e (EPS) insulation ad here d to or mechanicall y fastened over the gyps um boar d. The EPS or XPS is covered with glass fiber m esh, which is embedded in and covered with a base coat of po lymer- m od ified cement. A textured latex finish coa t is usually applied. Such systems should be tested in accordance with NFPA 285, including any architectura l finish es. It is common for faux beams and faux columns to be added over th e flat surface of the EIFS for aestheti c purpo ses. Often, th ese protrusions can be formed using EPS or XPS up to 1 or 2 ft (0.3 or 0.6 m) in either dim en sion, and in some cases finish es other than that tested and described above (such as po lyureth ane) m ay be proposed as a substitute, but th ey are not recommended . Fire loss exper ienc e is not favorable for such details that were n ot 7-14). successfully tested (FIGURE

FIGURE 7-13Steel girts.

FIGURE 7-14 Fire loss experience is not favorable for deta ils that were not successfully tested.

Floor/Ceiling Assemblies Fire safety in buildings is also influ enced by the floor/ce ilin g assembli es that must sup port th e dead and live loads placed on th em. Som e assembli es have b een tested in accordance with nationa lly recognized standards and h ave received a specific fire-resistance rating. Such assemb lies can be found in the UL Fire Resistanc e Directory (Volum e 1) or in the Gyps um Association's Fire Resistanc e D esign Manual. This rating does not mean th at they are impervious to fire for th e full rating period, however. For exampl e, rated stee l floor/ceiling assemb lies can easily be made ineffective by the remov al of 81

SECTION 2: Building Syst ems and Fire Protect io n Systems

ceiling tiles. The installed assembly must be identical to the assembly listed. Rated assemblies are tested only against fire from b elow when, in fact, fire can enter an assembly without hindrance either laterally or from above. When a floor/ce iling or roof/ceiling assembly is given a fireresistance rating, it is a rating for the total assembly, not the ceiling itself. Other assemblies ma y be combustible and may contain conc ealed spaces that are difficult to access and that allow for rapid fire sp read. The space between a ceiling and th e floo r or roof abov e may sometimes be used as part of the building 's air-h andling system or a convenient FIGURE 7-15 Space above ceiling used to hide piping, electri cal w iring, and co mmuni catio n loca tion to conceal electrical wiring, pip w iring. ing for domestic water supply, automatic sprinkl er systems, or com munic ation wiring (FIGURE 7-15). Co ntrol of combustible mat eri als in th ese spaces is tightly regulated by NFPA 90A, Standard for the Installation of Air-Conditioning and Ventilating Systems.

Roofs Roofing assembli es are constru cted of a combination of m ate rial s and in a varie ty of configurations . Basically, a roof cons ists of supp orts , such as beams or rafte rs, a deck, insul ation, and a covering . Environmen tal loads on the roof are carried by the roof deck and are transmitted along rafters and beams to the column s, founda tion systems, and soil below. Typical roof deck materials are concre te and steel in indu stri al and commerc ial construction and stee l and wood shea thin g in residential cons tructi on and smaller commercial projects. Insulation is generally mechanically fasten ed to th e top of steel roof decks and is covered on top by a roof cover ing that provides weatherproofing (FIGURE7-16). Roof cover in gs can be multi -ply, liquid app lied, or single -ply m embr anes. It is important to und erstand that there are two fire classifications for a roof assembly: one for underside fire exposure and one for exterior fire exposure. A built-up roof membrane typically cons ists of three to five layers, known as "plies;' of roof membrane attached to a wood or concre te roof deck or insulation and to each oth er at th e job site, with hot asphalt or some other adhes ive secur ing the layers. Ano ther type of multi -ply roof cover is the modified bitumen (or mod bit). This usually consists of two or three layers of heavier, polymer-modified asp haltic sheets, which may be sec ured using ad hesives, mechanical fasteners, or torc h-app lication. Torch -app licat ion of mod bits is a potential ignition source dur ing construction. Asphalt ad hesive or asphalt felt vapor barriers laid dir ectly on metal decking can allow fire spread on the deck un derside, which can result in collapse of unprotected steel framing, and shou ld not be used in this way. The use of

82

CHAPTER 7: Building Construct io n Element s

FIGURE 7-16 Insulation is mechanically fastened to th e to p of steel roof decks.

gravel surfacing or special coatings, such as asphalt emulsions or fibrated aluminum, will increase the resist ance of a built -up or m od -bit roof to exterior fire expos ure . Single-ply roof membranes generally consist of flexible, water -resist ant sheets of a var iety of plastic- or rubb er -b ased products . These m embran es are typic ally applied over rigid in sulati on. Reinforced m embranes are usually attached to the de ck with m echanic al fasteners . Unreinforced membranes are usually adhered or are ballasted with large gravel or concrete paving blocks. The spaci ng of fasteners is criti cal to th e wind -uplift resistance of th e roof. With sing le-p ly roof covers that are thin, the outline of the top of th e fasten er pl ate can usually be seen under th e membrane or b e felt by rubbing th e hand or foot over th e top of th e cover . Also, with stee l deck roo fs, viewing th e und ersid e of th e deck where fasten ers pene trate allows for a check of the fastener sp acin g. Differentiating between the various typ es of fastene rs used is imp ort ant. With mechanica lly att ached roof covers, som e fasten ers are used to secur e th e roof cove r to th e d eck; oth ers are used to fasten ri gid insulation below the cover to the deck. Also, fasteners found at the overlaps of steel deck sect ions, usua lly abo ut every 3.0 ft (0.9 m), are called side -lay fasteners and are used to conn ect adjoining deck section s but do n ot add any dir ect sec ur em ent for the insu latio n or roof cover. Elas tomer ic coa tin gs, suc h as acry lic, silicon e, po lyur eth an e, an d so on, are used as spray -app lied roof coverings over ur eth an e foam in sul ation, which is sprayed in place on top of the roof deck, exist in g roof cover, or therma l barrier. 83

SEC ION 2: Building Systems and Fire P1otection Systerns

Torch-aµplied roof systems are bitumin ous roofing systems that are heated with a torch (as it is rolled onto its substrate), which melts the asphalt that saturates the membrane. ·n1e membrane is then imm ediately secured to the substrate, usually a base ply, below. Guidance on safet)' in the use of torch-applied roof S)1Stems can be found in NFPA 24 1, Srn11dnrd }or Snfeg11nrdi11g Co11str11ctio11, Altemtio11,nnd De111oli tio11Opemtio11s.Nationally recognized standards exist to evaluate roof assemblies for interior combus tibility, surface burning over the top surfiKe, wind resistance, and hail resista nee. Roof assemblies that are rated as Class l or limited combust ible due to underside fire exposure are tested to FNI 4450, FM 4470, or NFPA 276 and can be found in FM Apprnvals RoofNav. I11s1dat cl ·t el decks may contain combustible above-deck components, as long as they are listed within the tested assembly. Whereas many aµµroved insulations may be fastened directly over steel deck. thermoplas tic insulation, such as XPS or EPS, requires a thermal barrier such as gyµsum board directly below the insulation and above the steel deck to achieve a Class 1 fire rating. Otherw ise, sprink ler protection may be provided directly below the deck. Some insulated steel deck assemblies that have not passed the above tests are considered Class 2, or combustible, due to the type and quantity of combustib le compo nents above the deck. Another classic example is any insulation that is secured clirectl}'to the steel deck with a full mop of asphalt. It is common in indus trial and commerc ial buildings to have a steel deck roof with a noncombustible or limited combustible suspended ceiling several feet (about 3 ft, or l m) below the roof deck and sprinklers below the ceiling. It is important to unders tand that the spri nklers below the ceiling will not be effective in controlling a fire within the concealed space. Class 1 insulated steel deck assemblies are suitable for Type I and Tyµe II constr uction; Class 2 steel deck assemblies are suitable for Type Ill, Type lV, or Type V construction. Thermoplastic insulation used over a therma l barrier on top of steel deck can be considered li1nited combustible and is acceptable for Type I or Type 1I const ruction. AST:rv(E 108, FM 4470, and UL 790 are tests used to evaluate fire performance of roof coverings exposed to e;derior fire and rated as A, B, or C. A Class A rating is the best rating and is preferred where exterior fire exposure may be significant. Codes allow the use of a Class 13or a Class Crating in many applications, which explains why some fires i.n urban areas or wooded areas spread to multiple buildings. Examµles of fire-retardant Class A coverings are brick, exposed concrete, concrete paver blocks, and concrete or clay tile; fiber-reinforced cement tile; slate; and copper or steel panels/shingles. l arge stone used on ballasted roofs or a mi11imum of 4 lb/ft2 (20 kg/m2) of pea gravel (¾to½ in. diameter; 0.95 to 1.25 cm diameter) embedded in a flood coat of asphalt or coal tar are also considered to be Class A coverings (FIGUR E 7-17). Fi.re retardant- treated wood shingles FIGURE 7-17Class A coverings. are recommended over unt reated wood 84

CHAPTER7: Build ing Construction Elements

shingles. Also, fire retardants may be lost over time due to weathering; replacement is recommended at the end of their life span. Untreated wood shingles have been used in the past but are now proh ibited in many communities because they ignite readily and can produce fire brands, which may ignite surrounding combustibles and buildings. Some smooth-surfaced, bituminous roofs use coatings such as fibrated aluminum and asphalt emulsion to improve exterior fire resistance. Tests to dete rmine hail resistance include FM 4470 (moderate or severe hail), FM 4473 (Class l, 2, J, or 4 hail), or UL 2218 (Class I, 2, 3, or 4 hail). A Cla s 2 hail rating, or "moderate" rating, is based on resistance to hail of 1½ in. (3 .8 cm) diameter. A Class 3 hail rating is based on exposure to hail of l ¾ in. (4.4 cm) diam eter, and a Class 4 hail rating is based on exposu re to hail of2 in. (S cm) diameter. A Class 3 or 4 hail rating is recommended for areas prone to severe hail. FM 4470 is also used to evaluate winduplift resistance of roof covers. Ratings are 60 psf (2.86 kN/m2), 75 psf (3.58 kN/rn2), 90 psf (4.30 kN/m 2), 105 psf (5.02 kN/m2), 120 psf (5.7'1 ki\l/m 2), and so on. (Note that psf stands for pounds per square foot.) 1l1e required rating (psf) is based on the roof height, geographic wind speed, and ground roughness exposure {surrounding terrain). Environmental concerns have made "vegetative roof systems" or green roofs and solar photovoltaic roof panels popular recently. Information on green roof systems can be found in FM Global Data Sheet 1-35, Green Roof Systems. Requirements can also be found in FivI 4477, Approval Standardfor Vegetative Roof Systems. Roof-mounted, solar photovoltaic systems are either flexible, which can be adhered to approved roof systems, or rigid. Rigid systems are usually ei.ther loose-laid or ballasted when used over si11gle-ply or multi-ply roof covers and are clamped to standing seam roofs (FIGURE 7·18).Such systems can be a potential ignition source and, in some

FIGURE 7-18Rigid systems are either loose-laid or ballasted over single-ply or multi-plyroof covers and are damp ed to standing seam roofs.

85

SECTION2: Building Systems dlld Fire Proteclion Sy:.te,11>

cases, an additional so urce of fuel for a roof fire. Rigid systems can also pose a potentia l obstruction to fire-fighter roar access, making the provision of apµroved aisle spaces cr itical. Often, rigid systems are installed on existing roofs with minimal excess load capacity. TI1is limits the amoun t of ballast that can be added and, in some cases , may make these panels suscept ible to blow off in high wind s. Systems may be tested to UL 1703 for elect rical requirements and Fi\!l 4476 and 4478 for other requirements , includ ing wind resis tance. See Chapter 6 for add itional information on g reen roof des igns .

Fabric and M mbran

tructur s

Fabric and membran e structures have become more and more popular as either temporary or permanent stru ctur es . Thes e are used comp letely or partially lo enclose a number of occupanc ies including the top level of park ing structures, sports arenas, and sports pra ctice facilities. Usua lly, the fabric is either Teflon-coated fiberglass (TCF) or polyvinyl ch lo ride (PVC)-coated fabric. TCF is not conside red a combustib le material, whereas PVC-conted fabric has a low softening temp eratur e and will burn to varying degree s depending on the formulation. Where PVC -coated fabri c is used to enclose a sprinklered structure, quick-response sprinklers are preferred (FIGURE 7-19). Structural suppo rt for the se fabrics is either from steel cables or beams, air -supported, or a combination of air - and cab le-supported.. Fabric structures that are air -supported, in whole or in part, are historically not structurally reliable . Tiiere have been numerous occurrences of collapse in wind or snow storms , as they are reliant 011 mechanical and elect rical power to stay up . For additional informat ion , see publicat ions by the ASCE. See Building Co11s/ructio11 for the Fire Sen'ice and the Fire Pmtcclio11Hn11dbookfor additional information on structural elements.

FIGURE 7·19 Quick-response sprinklersare preferred when PVC-coated fabric is used.

86

CHAP ER 7: IJuilding Construction Efernents

IBLIOGRA HY AISC SteelDesignlvlan11al,13th ed., American Jnstitute of Steel Construct ion, Chicago, IL, 2005. APA, Wood I-JoistsFloors, Firefightersa11dFire, Technical Topic TT-OJSE, September 2010. Available at: http://www.apawood.org. ASCE/SEI 17-96, Air-Supported Structures. ASCE/SFPE 29-05, Stn11dardCalculationlvfethodsfor Strnct11rnlFire Protectio11,2005. ASCE/ T&DI 55-10, Tensile Me111brn11 e Strnctures. ASTM E- 108, Standard Test1\tlethodsforFire Tests ofRoofCoveri11gs,2010 . A T 1VI E-605, Standard Test Metlwrlfor 711i (k11ess and De11 sity of Spmy cd Fire-U.esistil'e Material (SFR.M)Applied to Struct11rallvle111bers, 1993 (2006) . AST!vl E-736, Standard Test Method for Cohesio11/Adhesio11 of Spmyed Fire-Resistil'e Materials Applied to Structuml lvfe111bers, 2006 . Bran n igan, F. L., B11 ilrli11 g Co11 str11c tio11fo r the Fire Serl'ice, 4th ed., NF PA, Quin cy, MA,200 7. Building Materials Directory, Underwriters Laboratories, Inc., Northbrook, IL (issued annually). Cote, A. E., ed., FireProtection Handbook, 20th ed ., NFPA, Quincy, MA, 2009. FM Approval Guid e, Building Materials \fol11111 e. An online resource of FM Approvals. Available at: http://www .approvalguid e.com FM RoofNav. An onlin e resource of FM Approval s. Available at: https://roofnav.fm global.com/RoofNav/Login .aspx FM 4450, TestStandardfor Class 1 I11srilat ed Steel T' timber construction if they are more than 30 ft (9.1 m) from the property line and provided th at the 2-hour fire-resistance rating is maintained. During a fire, heavy timb er construction performs better than do conventional wood -fnune structur es becaus e the structural m embers are larger, have a smaller sur face -to -mass ratio, and take longer to burn , As the wood memb er burns, a layer of char develops , which acts like insulation and slows down th e rate of burning. The large wood memb ers, therefore, can continue to catT}' their structural loads for longer dura tions due to the mass of unburned wood. Heav y timb er construction is more appropriately considered a building system, not ju st a constru ction type using large -size structural m emb ers . It was dev eloped during the rnid - 1800s by in suran ce int erests for th e purpo se of reducing fire los ses in the m any lextile factories, pape r mill s, and storag e buildings in the New England states . Throu gh the intelligent use of co mbustible m aterials of sufficien t ma ss, th e absence of concealed spaces, and by payin g attention to detail s to avoid sharp corners and ignit able projections, fire sp rea d and serious structural damage pot enti al are lessened with respect to ordinary wood framin g. Examples of heavy timber construction are shown in FIGURE 8-2 and FIGURE 8·3.

96

CHAPTER 8: Classification of Constru ction

Types

FIGURE 8-2Elements of a building of Type IVconstruction. Note the large sizeof the columns and beamsand the absence of concealed spaces.The exterior wall at far left is of lightweight corrugated steel.

TYPE V CONSTRUCTION 1)rpe V cons truction is a type of construction in which the structural members are en 8-4). Depending on the exter ior tirely of wood or an}' other approved material (FIGURE horizontal separation, the exterior walls may or may not be requir ed to be fire resistive. In Type V construction, walls and par tition s are typically framed with 2 by 4 in. (5.1 by 10.2 cm) wood studs attached to wood sills and plates. \\ 'ood boards, plywood sheets, various compos ition boards such as oriented strand boards (OSB) or other approved materials are th en nailed to the studs. Over this underlayment is placed a layer of building paper and then th e finished material. The exterior wall cover ing can be any one of a variety of mat eria ls, including wood shingles, wood clapboards, plastic (polyvinyl ch lorid e), metal clapboards, matched boards, brick veneer, sheet metal clad d ing, stucco, or fiber-rein forced cement pane ls. 97

SECTION2: Build ing Systems i!ll(I FireProtection Systems

FIGURE 8-3 Variation ofType IVconstruction. Shown are haunched archesmade of laminated wood (glue-laminated construction). Beamsare anchored to the arches by steel hangers. Framing system of a representative building of Type II noncombust ible construction.

Type V construction is more vulnerable to fire, both internally and externally, than any other building type. TI1isis reflected in the height and area limitations that restrict this construction type to relatively small footprint buildings that typically do not exceed 4 stories. According!)', it is essential that greater attention be given to the details of construction of this basically light wood-frame building. The use of fire blocking in exterior and interior walls at ceiling and floor levels, in furred spaces, and in other concealed spaces can retard the spread of fire and hot gases in these vulnerable areas. Type V construction is subdivided into two subcategories: Type V ( 111) construction, which has I-hour fire-resistance rating throughout, including the exterior bearing walls, and Type V (ODO)constrnction, which has no fire-protection or fire-resistance rating requirements, except for the exterior walls, which may not have such a requirement depending on the building occupancy and horizontal separation distance to adjacent structures.

98

CHAPTER8: Classification of Co11 s11uctianTypes

n

(a) Plank-and-beam framing

(b) Conventional wood framing

FIGURE 8-4Twovariations on basicTypeV construction:(a)plank-and-beamframingwith a few large members replacingmanysmallmembers used in typical wood framingand (b) 1c e:RreP 101eaionH011dboot llFPA , conventional wood framing(western or platformconstruction).Sou 20thed.,Figure 19.1.4,(a)and(b).

MIXED TYPESOF CONS RUCTION Where two or more types of construction are used in the same building, it is generally recognized that the requirements for a particular occupancy or the height and area combination would apply for the least fire-resistivetype of construction. However,in cases where each buildi11gtype is separated by adequate fire walls (see NFPA 221, Stnndnrdfor High ChnllengeFire Walls,Fire Wn/1s,and FireBMrier Walls)having appropriate fire resistance, each portion may be considered as a separate building. In most cases, the codes will requires that this separation have a rating ofat least 2 hours. Another general limitation included in some model building codes prohibits con struction types of lesser fire resistance to support const ruction l}rpes having higher required tire resistance. Jn the event of a fire, the risks of a major structural collapse are generally too great to permit this type of design. TI1is limitation does not necessaril}' apply where construction supports nonbcaring separating partitions tha t provide protection for exit corridor s or tenant space .

BIBLIOGRAPHY ASTM E 84, Stnndard Test 1vlet/10dfor Surface Burning Cliamcteristics of Building 1Waterinls,2010.

AST.M E 119, Standard Test 1Wet/10ds for Fire Tests of Building Co11structio11 n11d Mnterinls, 2009. 99

SECTION 2: Building Systems and FireProtection Systems

Brannigan, F.L., Building Constructio11 for the FireService,4th ed., NFPA, Quincy, MA , 200 7. Building Materials Directory, Underwriters Laboratories, Inc ., Northbrook, IL (issued annually). Cote, A. E., ed. , FireProtectionHandbook, 20th ed., NFPA, Quincy, l'vlA, 2008 . FM Approval Guide, Building Materials Volume. An on line resource of FM Approvals. Fire Resistance Directory, Vol. 1, Underwriters Laboratories, Inc., Northbrook, IL (issued annually). NFPA Codes, Standards , and Recommended Practices Sec the latest version of th e N FPA Catalog for availability o f curren t editi ons o f th e following documents.

NFPA 220, Standard on Types of Building Construction NFPA 221, Standardfor High ChallengeFire Walls,Fire Walls,a11dFireBarrier Walls N FPA 24 1, Standardfor SafeguardingConstruction, Altemtion, and Demolition Opemtions N FPA 259, Standard Test Methodfor Potentinl Hent of BuildingAfaterials NFPA 703, Standardfor Fire-Retardant Treated Wood and Fire-Retardant Coatingsfor

Building i\foterials

100

CHAPTER

9 CONSTRUCTION, ALTERATION,AND DEMOLITION OPERATIONS Richard]. Davis, PE, FSFPE

Fire inspectors are frequently faced with hazards introduced during construction, altera tion, and demolit ion operations. Most buildings are more vul nerab le to fire at these times than at any other because the amount of combustibl es and hazardous material s and the number of potential igniti on so urces pre sent are often grea ter th an usual, and the facility's fire protec tion systems may be impaired or not yet operative. Many of the comme nts to follow cou ld apply to two or even all three of these factors .

CONSTRUCTION Construction projects progress more rapidly in areas import ant to fire protection once basic foundation walls are completed and the building begins to take shape. Thus, they should be insp ected more frequently after framing is under way. How ever, planning and scheduling to ensure tha t water supplies are available for fire con tro l during construction must be reviewed during the planning and permit stages. Myriad other systems and features are needed, such as access roads, water mains, temporary water storage, sprink ler systems, hydrants, and sta ndpipe systems for multistory buildings. Use and availability of portable extingui shers for contractors, fire watch services, and timely comp leti on of fire walls are proper!}' planned and physically in place when needed. Making sure that the fire protection stra tegy during cons truction is clearl y laid out in the plans and specificat ions or is included in the permit conditions can prevent many prob lem s, ra ngin g from dis agreements to major fire loss during construct ion . All of these points are eq uall y important during bui lding deconstruction or demolition operations as sho wn in th e 2007 De utsch e Bank fire in New York City tha t resulted in the death of two fire fighters. TI1ebuilding owner or contractor shou ld appoint one individua l to oversee all fire protection duties.

SECTION 2: 13uildingSystems and Fire Protec tion Systems

Site Preparation In large projects, site preparation should include not only the removal of vegetation and combustible debris from the site, but also the appropriate layout of the contractors' temporary buildings, trailers, material storage yards, and waste storage so that they wiJI be neither a fire exposure to new construction nor obstruct accessroutes for fire fighters and their equipment. Most codes contain provisions that can be invoked to cover problem areas, but such after-the-fact solutions are seldom as satisfactoryas planned layouts. Roadways with an all-weather driving surface should be provided for fire apparatus. 1l1eyshould have an unobstructed width of at least 20 ft (6.1 m) and have at least 13 ft 6 in. (4.1111)of vertical clearance. rf permanent water mains and hydrants cannot be installed during the site preparation and foundat ion phases of the project, temporary water supplies, such as onsite tanks or tank trailers, temporary or surface mains (temperature permitting), and pumps, may have to be included in the project cost. Aboveground swimming pools make excellent temporary water storage and can be moved easily as needed. It is important that these items, which could involve substantial cost, be included in the overall project cost. Temporary water supplies must be properly located to protect against damage from constr uction equipment or activities, and they should be designed with protection against freezing or other site-specific perils. If special equipment, such as pumps or normally closed water supply lines, is present, guards, a fire watch, or other persons on site 24 hours per day might be recommended and they must know how to operate any such equipment. 1l1ismeans knowing not on!)' how to start a pump but also how to prime it, if necessary, and understanding which valves need to be kept open or closed.

Temporary Structures Nearly all temporary strnctures associated with construction projects are made of combustible construction, whether they have a metal or plywood skin or ride on trailer wheels or skids. They will burn rapidly and can be the source of a major loss. In the worst situation, a temporary stru cture, such as a job office, a tool or supply shed, a warming or locker room, or a carpenter or paint shop, is set up within the structure under construction. A fire in such a temporary structure can quickly spread to or otherwise damage the major structure. Because this approach is favored by contractors for ease of travel, security, economy, and weather protection, it can become the norm unless the regulatory agencies resist it. TI1esituation is more difficult to handle at an urban site, where space in the streets is limited or nearby buildings must be rented at significant cost. If space is available, the temporary units should be separated by 30 ft (9.1 111)or more (depending on the size of the exposing unit) from the main building and from each other to minimiz e the loss potential from a "shack" fire. However, this amount of space can easily require many acres, so a compromise is generally necessary, depending on the hazard, value, protection, and construction features of both the temporary and permanent structures . Tempora ry enclosures of coated fabric or plastic are often used to protect workers and construction operations from the weather until the building is enclosed. They 102

CHAPTER9: Construction , Alteration, and Dem olit ion Operations

can help to maintain heat within the building frame area, as well as keep debr is and dirt o ut. It is important that they remain int act so tha t the)' help prevent freeze-up of mat erial or eq uipn1ent within and to show that they are not torn and blown against temporary heating eq uipment. If fabric is used, the inspec tor sho uld make sure th at it is made of a material that will not allow fire propagat ion withi n itself. If plastic is used , it should be flame resistant and pass Test No. 2 not ed in NFPA 70 1, Standard Methods o.fFire Tests.for Flame Propagationo.fTextilesand Fi/111 s. Depending on the length of time the enclosure will remai n in place and the potential exposure to wind, a material that is resistant to ultravio let rays and reinforced or othe rwi se of su itab le strengt h is desirable so that it does not fall apart or tear before it is no lon ger needed. The mater ial should be fastened secur ' ly to the building frame to preven t it from being torn by the wind and comi ng i.n contact with an ignition source, such as a temporary heater.

Pro e

Ha za rd

Although some process hazards are inherent in such job-site shops as ca rpenter, weld ing, pipe, and pa int facilities, the inspec to r can encourage segregati on of incompatible uses, such as ca rp entry and welding, and discourage th e accumulation of flammable liquids in paint, fuel, and lubrica tion areas. Substandard heating appliances, stovepipes, bonfires, and substa nda rd liquid or gas fuel- hand Ii ng systems are proven fire hazards and sho uld not be tolerated. If local fire codes do not provide the au thorit y to cope with these problems, the adopt ion of stronge r codes should be enco uraged . Nationa l. Fire Protect ion Association {NFPA) codes and standards that provi de specific fire safety criteria add ressing specific hazard s, such as NFPA 1, are available (see the Bibliography) .

Housekeeping Prompt removal of trash and construc tion debris from a construction or remode ling site is critical to fire safety. Because it is an overhead cost to the con tract or, however, the inspector mus t often take a firm stand to ensure reasonable compl iance . Jf trash chutes are used, they shou ld be located on the outside of the building . They shou ld be of noncombus tible construction and as straight as possible to prevent debri s from piling up inside . Storage of combus tible consh· uctio n mate ria ls, scaffolding materials, or formwork on site can present both a fire exposure and an imp ediment to first responder and emergency access. It can eq ually hind er the escape ro utes for workers who would have to leave durin g a fire emergency. To prevent this from happ ening, large amou nts of combus tible mater ials should be well separa ted from the build ing. An inspector can have consid erable influ ence on material storage and delivery practices.

Theft and Vandalism Althoug h there is no one absolute prevention measure, a clean job site that is fenced, secured, lighte d where needed, nnd nttended by guards is mu ch less likel>'to experien ce 103

SECTION2: Building Systems and FireProtectionSystems

a fire started by a th ief or vanda l. Where on-site watch service is not practical, consideration may be given lo providing remote-site video surveillance. Again, a realistic balance of cost and exposure is necessary.

Other Hazard s TI1enumber and size of engine-driven forklifts, crew lifts, excavators, and so on, all of which must be refueled on site and all of which contain hot exhaust S)'Stems capable of igniting trash, spilled fuel, or plastic weather enclo ures, are significant. The person handling job-site safety for the general contractor should en force and require in wrilingjob -sile safety rules on fuel storage and handling, equipment shutdown during fueling, and fire extinguisher availability. A fuel-dump arran gement and fuel-handling rules also must be designed for the site. Fuel should be stored separately from the building under construction and from major temporary structures, and indoor fueling should be restricted to devices that ca111iolbe moved readily. Only those fueling S)'Slems that minimize accidental spills, such as safety cans, automatic shut-off nozzles, and approved pump systems, should be used, and extinguishers should be provided according to NFPA 10, Stnndnrdfor Portable FireExtinguishers. Further discussion of fuel storage and handling can be found in this text and in NFPA 30, Fln111 111nbl e and Co111b11stibl e Liquids Code. Hot work including open flame and spark-producing equipment , such as cutting torches, arc welders, soldering and grinding tools, and roofing fusion machines, must be strictly controlled. TI1ebasics of fire prevention are simple: combustibles within a 35-ft (10.7-m) radius of or below work areas must be monitored, the equipment used must have the proper safety controls, a fire watch must be used, and extinguishers and ho ses must be readily available (FIGURE 9-1). Still, hot-work fires in construction projects are frequent. In situations where it is not practical to remove all combustibles that may be exposed to hot work, they may be covered with approved welding pads, blankets, or curtains as tested in accordance with American National Standards Institute (ANSI)/FM 4950, A111erica11 Nntio11nlStnndnrd for Evnl11nti11g WeldingPnds, Welding Bln11ketsn11dWelding C11rtni11s for Hot Work Opemtio11s.Definitions and uses for weld~ ing pads, welding blankets, and welding curtain s are as follows. Welding Blanket. This is a heat-resistant fabric designed to be placed in the vicinity of a hot-work operation. It is .intended for use in horizontal applications with light to modera te exposures, such as that resulting from chipping, grinding, heat treating, sandblasting, and light horizontal welding. It is designed to protect machinery and prevent the ignition of combustibles, such as wood, that are located adjacent to the underside of the blanket. Welding Curtain. TI1is is a heat-resistant fabric designed to be placed in the vicinity of a hot-work operation. Tt is intended for use in vertical applications with light to modera te exposures, such as that resulting from chipping, grinding, heat treating, sand blasting, and light horizontal welding. It is designed to prevent sparks from escaping a con.finedarea. 104

CHAPTER9: Construction, Alteratio11,and Demolition Operatio11s

FIGURE 9-1 Fire watch monitori ng a hot -work area.

Welding Pad. This is a heat -resistant fabric designed to be placed directly und er a hot -work operation such as welding or cutting. It is intend ed for use in horizontal applications with severe exposures such as that resulting from molten substances or heavy horizontal welding. It is designed to prevent th e ignition of combustibles that are located adjacent lo the underside of the pad. further discussion of hot-work hazards and contro ls can be found in Nf PJ\ 5 1, Stn11 -

dard for the Design and lustnllatio11of Oxygen-Fuel Gns Systemsfor Welding, Cutting, and Allied Processes;NFPA 518, Stn11dnrdforFirePrel'e11tio11 D11ri11g Weldi11g, C11/lil1g, n11dOther Hot Work; and NFPA 241, Standardfor Safeguarding Co11strnctio11, Altemtio11 , a11dDemolitio11Opemliom. Roofing materials, whether the older ho t-mopped felt, tar, and gravel system, the torch -app lied modified bitumen, or the cold-applied cut back asphalt system, all have a common problem-much of the work is don e with flammable materials that are heated near or above their flash points. \iVorkers who a re care less with torches, inac curate or nonexistent controls for aspha lt po ts, or cigare tte smoking provide potential sources of ignition. The inspector should not allow torches to be used near areas in whi ch combustible dusts or oils may accumulate, such as exha ust hoods. Propane tanks on which frost has built up should not be heated with the torch flame . Instead, a large r tank should be recom mended. Strict contro ls are necessary on the location and temperatur e co ntrol for a phalt pots. The pots should never be placed on the roof

105

SECTION 2: Building Systems and Fire Protec tion Systems

or under roofs or canopies, and their temperature controls must be automatic and working properly. NFPA 241 contains guidelines for fire-safe roofing operations. For additional information, refer to FM Global Property Loss Prevention Data Sheet 1-33, Snfeguarding

Torch-Applied Roof lnsta/latio11s. Needless to say, application and kettle areas must have a sizable (2-A:20-B:C) portable extinguisher within 25 ft (7.6 m) to 20 ft (6.1 m) (the latter for torchapplication equipmen t) of the immediate work area because a roofing fire can be just as hot and spread just as rapidly as any flammable liquid fire. If attempts to extinguish a kett le fire with hand extinguishers are unsuccessful, water from a hose lin e must be appli ed in a fine spra y because of the po ten tial frothing action of hot asphalt. Roofing mops soaked with tar have been known to ignite spontaneously and cause fires. Used mops should not be left indoors or near ignition sources or combustible materials. Rather, they should be "spun" or cleaned thoroughly and safely store d or properly disc arded. Although exterior cavity walls have been used for decades, they have become more popular over the past few years to prevent the development of mold within exterior walls. 1l1ese walls typ ically have a 2 in. (5 cm) space between the exterior side of the insul ation and the interior side of the fac;ade. Often, the insulation within these cavities is highly combustible foam plastic. Although expanded glass and mineral wool (rock wool) can be used in cavity walls and are noncombustible, extruded or expanded poly styrene is often used, as is expanded polyurethane. 1l1ere also may be no fire-stopping in either the horizontal or vertical direction in existing construction, so extreme caution is necessary regarding hot work. Although such insulation may be protected from an exterior or interior fire because of a fire-resistive fac;ade or interior sheathing, the insulation could be ignited from hot work within, above, or near the cavity. Exterior wall assemblies may be tested in accordance with NFPA 285, Standard Fire TestMethod

for Evaluation of Fire Propagation Characteristicsof Exterior Non-Load-Bearing Wall Assemblies Containing Combustible Components, but that test does not include any fire exposure within the cavity space. For additional information, see FM Global Data Sheet 1-12 and FM Approval Standard 4411 .

Fire Protection When NFPA 101®, L(leSafety Code®,or the building code requires that a building have standpipes, they should be installed on a floor -by-floor basis and in accordance with NFPA 14, Standardfor the Installation of Standpipe, Pri11ate Hydrant, and Hose Systems. NFPA 14 provides a specific set of design and installation rules for buildings under construction. TI1e standpipe can be either temporary or permanent (and rigged as a dry standpipe in cold climates) until the building is enclosed and heated. In most cases, the fire department connection must be temporary, because the permanent location will not be completed and might not be accessible during much of the construction. Regardless of the type of building under construction, portable extinguishers must be provided in rating and spacing suitable to the construction activit}' and in accordance with NFPA 10, Sta11dardforPortableFireExtinguishers. 106

CHAPTER 9: Const ruction, Alteration , and Deniol ition Operations

Sprinklers should be put into serv ice and fire walls or fire barrie r walls should be buil t as soon as poss ible afte r the building she ll is finished . Only steel, fire retardant treate d wood, or limited amounts of combustibl e form work , scaffolding , or shor ing are acceptable in unsprinklered areas.

ALTERATIONS AND AD

IONS

More o lder buildi ngs are bei ng altered or renovated, some to p reserve th e arc hit ecture of an age gone by. As ol.der bu ildin gs are rehabi lit ated, every effort shou ld be made to brillg them i11tocompli ance with pr esen t-day buil d ing and fire codes. However, this is not always possible. In such cases, eq uivalen t prot ect ive measures might be acceptab le il1 lieu of meeting certa in code requir ements. l11ese equ ivalencies might involve the installat ion of auto matic sprinkler protection, smoke detection systems, and smoke con tro l features. Fire insp ectors are res pons ible for policing th ose prot ect ion system s as th ey would th ose in a new bu ildi ng. Some tim es, renovations are made while a build ing is part ially or folly occup ied. lt is extremely impo rt ant for life safe ty purposes that exits for occupan ts are properly maintained. lt is the inspector's job to make sure that the exits are accessible from th e work area and have been properly iden tified. In addition to exits for occupants, sufficient means of egress should be provided for construction workers in th e area under renovatio n, in accordance wi th the Life Safety Code®. Remember, these same egress access ro utes will also be used by first responders to gain access to the work area should a fire or other emergency occur. Inspecto rs should be just as dili gen t in inspecting these means of egress as they are in inspec ting the p ublic exits in any building . If a build in g cons truction/ demolition proje ct blocks an existing exit, an alternate mean s of egr ess must be provided. The inspecto r must scrutinize the alterna te route to make sure it is usab le in case of an emer gency. TI1e exit should be free of debris and stored materials; it shoul d be properly identifie d and illum inated and the exi t d ischarge should be clea r of parked vehicles and oth er obstructions. In some cases during alterations , existing fire-resistive floor or wall assemblies may be penetrated by new piping or condui t or old piping or conduit may be removed . In either case, it is impo rt ant that fire-resistive p enetratio n seals be provided after this is done to maintain th e fire in teg rity of the subdivisi on (see FIGURE 9-2). In so me cases, plastic wrap s are used in the interior of an existing building to protect existing equipment and supplies from dust and debri s. Such wraps must be sim ilar!)' tested pe r NFPA 701, as described earlier. In addition, it is imp ortant that these wraps do not potentially obstruct spri nkler water flow to combustibl es below. Otherwise, all combustibles should be remove d from the area. If the altera tio ns involve hot work , such as cutt ing, welding, and heating, a permit system sho uld be used; for furth er inform ation, see NFPA SIB . Whenever practica l, combustibles should be removed from at least 35 ft ( 10.7 m) in all directions. If this can not be done, th e in spec tor sho uld recommend covering combu stibles with an approved fire-resistant tarp, sweepi n g up combustible dusts, and wetting down wood floors. Use tarps that have been tested to ANSI/FM 4950. Products tha t have passed this test can be found in th e Fi'vlApproval Guid e, and th ese items were describ ed ear lier. 107

SECTION2 : Building Systems and FireProtection Systerns

FIGURE 9-2Fire-resistive penetration seal.

A fire watch provid ed with extinguishers or hoses should be assigned to the area for the duration of the work and at least 30 minute s after the work has been finished; this time period sho uld be extend ed to 2 hours for torch-applied roof installation s.

DEMOLITION Demolition operations have many of the previously noted attendant hazard s of construction operations, as well as a few others. 'foe hazards of cutting torches, flammable liquids, and tra sh accumulations are as common in demolition operations as they are in construction operations. Before demolition beg ins, gas pipes sho uld be turned off and capp ed outside the building. Explosives shou ld be sto red and used in accord ance with NFPA 495, faplo-

sil'e lvfnterialsCode. Early in a demolit ion project, flammabl e liquids and combustible oils should be drained from tank s and machin ery and imm ediately removed from the buil d ing. The removal o f residue and sludg e deposit s and purging of flamm able vapor s is also impor tant, especially in areas where cuttin g torches are used. Torches should no t be used to cut through walls, floo rs, ceilings, or roofs con taining comb ustib le materials. Fixed fire protec tion systems and fire walls shou ld be maintained in service for as long as po ssible. Sprin kler and sta ndpip e systems should be modified so they can be dismantled floor by floor as demolition progr esses downward from the top floor or 108

CHAPTER 9: Cor,struct ion, Alteration , and Demolition Operations

system by system in large one-story buildings. 1h is will preserve protection in the adjacent floors or areas. Either type of protection can be converted readily from a wet-pipe system to a dry-pipe system if minima l heat (40°F, or 4.4°C) cannot be maintained at remote parts of the building. Generally, chutes are provided to carry demolition rubble and debris from the upper floors to trucks or mobile trash receptacles below. These should be constructed as described in the earlier section on housekeeping. The use of inside chutes, which would necessitate cutting holes in the floor, thereby creating an unprotected vertical opening through which fire coul.d spread rapid!)' from floor to floor, should be discouraged. Implosion is sometimes used to complete demolition of multistory buildings. Design and implementation of such an event should be limited to those trained and experienced in it. [n addition to providing safety for explosives as described earlier, this requires a thorough review of the structural framing system and proper sequencing of explosives initiation to allow the building to come virtual!)' straight down. This also requires an evaluation of the separation from adjacent structures and potential impact to the surrou nding infrastructure. Sometimes, this requires the removal of some of the struc tural eleme11tsand/or the addition of cabling to ensure the frame collapses inward. Depending on the building height and weight and exposure to underground services, in some cases sand has been provided on the surrounding grade level to dampen the imp act and prevent damage to underground water mains, gas lines, and so forth. Charged hose lines of sufficient length to extinguish any subsequent small fires should be readied prior to demolition.

UNDERGROUND OPERATIONS General A num ber of the guidelines mentioned earlier for construction, alteration, and demolition operations apply to underground operations as well. However, other concerns also apply to these operations. Strnctures and equipment should be constructed of noncombustible materials as much as is practical. Because of possible changes in underground operations, it is important to maintain current written procedures for evacuation, fire prevention inspections, and other emergency procedures.

Fire Protection A water supply should be provided wherever combustibles are present. Outlets with standard fittings compatible with local fire departm ent equipment should be provided so that the maximum travel distance to a hose connection does not exceed 150 ft (46 m). Drainage systems should be provided to remove sprinkler and fire hose discharge. Underground operations that use equipment or components that transport materials to the surface using a conveying system will require specialized protection measures. Extinguishing equipment should be provided for belt conveyors at their head, tail, drive mechanism, and take-up pulley areas and at maximum intervals of 300 ft (91 m) along their length and along the tunn el, such that the maximum travel 109

SECTION 2: Bui ld ing Systems and Fire Protec t ion Systems

distance on a h orizont al plan e does not exceed 300 ft (91 m). Ar eas n ear and und er belt conv eyors sh ould be kept free of accumulating combu stibl es. Int erlocks should be prov id ed to shut down th e conveyo r dri ve on activ ation of any fire pro tec tion system or on stopp age or slowd own of th e conv eyor belt.

Flammable and Combustible Liquids Class I flamm able liquid s sh ould n ot b e permitt ed und ergro und or within 100 ft (30.5 m) of a tunn el p ort al or shaft openin g. Storage of oth er flamm ab le liquid s should be dik ed or oth er wise p ositi oned so th at spill s will n ot flow away from th e storage area.

Security and Compartmentation A check-in /ch eck-o ut system should be provid ed at each und ergro un d entr ance for each person in tr an sit to and from the und ergro un d op er ation . Sections of und ergro und that are n o long er in use should be b arrica ded and m arked. Fire and sm oke ba rri ers sh ould be used to limit fire spr ead and to prov id e areas of refuge for occ up ant s wher e egress is n ot pra ctical.

Electrical Equipment Electri cal equi pm ent sh ould be pro tected agai nst physica l dam age and suitable for damp loca tions. Oil -filled tr ansfor m ers sh ould not be used und ergro und unl ess th ey are en close d by fire-r esistant m ateri als, vent ed to th e ou tside, and dik ed to cont ain the ent ire con tent s of th e tr ansformer.

BIBLIOGRAPHY AN SI/ FM 4950 , American National Standard for Evaluating Weld ing Pads, Welding Blank ets and Weld ing Curtains fo r Hot Work Op erations. Co te, A. E., ed., Fire Protection Handbook, 20th ed., NFPA, Quincy, MA, 2008. Fisher, G. L. "Gettin g Thro ugh Co nstru ction ;' Fire Prevention , No. 248, Apr il 1992, pp. 20- 22. FM 44 11, Insu lated Wall Cons truction, 20 11. FM Global Property Loss Preventi on Data Sheet 1- 12, Ceilings and Conc ealed Spa ces, May 2008 . FM Globa l Prop erty Loss Preve ntion Data Sheet 1-33, Safeguarding Torch-Appli ed Roof Insta llations, Septembe r 2000 . Gray, J. A., and Ardit i, D., "Fire Pr evention and Protect ion Du ring Const ru ction; ' Journal of Appli ed Fire Science, Vol. 4, No. l , 1994- 1995, pp. 53- 68. Tremblay, K. J., "Sparks fro m Saw Ignite Chur ch Balcony;' NFPA Journa l, Nove mb er/ December 1999, p. 17. Wolf, A., "Sevente en Die in Dus seldorf Airp ort Termina l Fire;' NFPA Jour nal, July! August 1996.

110

CHAPTER 9: Constructi on, Alterati on, and Demolition Ope rations

NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Catalog for availability of current editions of the following documents. NFPA 1, Fire Code NFPA 10, Standard for Portable Fire Extinguishers NFPA 14, Standard for the Installation of Standpipes and Hose Systems NFPA 30, Flammable and Combustible Liquids Code NFPA 51, Standard for the Design and Installation of Oxygen-Fuel Gas Systems for Welding, Cutting, and Allied Processes NFPA 51B, Standard for Fire Prevention During Welding, Cutting, and Other Hot Work NFPA 54, National Fuel Gas Code NFPA 58, Liquefied Petroleum Gas Code NFPA 101®, Life Safety Code® NFPA 122, Standard for Fire Prevention and Control in Metal/Nonmetal Mining and Metal Mineral Processing Facilities NFPA 241, Standard for Safeguarding Construction, Alteration, and Demolition Opera tions NFPA 285, Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Non -Load -Bear ing Wall Assemblies Containing Combustible Components NFPA 495, Explosive Materials Code NFPA 701, Standard Methods of Fire Tests for Flame Propagation of Textiles and Films

111

CHAPTER

10 PROTECTION OF OPENINGS IN FIRE RATEDASSEMBLIES Kristin Collette Bigda, PE, MSFPE

Limiting the spread of fire and smoke is critica l to both life safety and property protectio n. One met hod of limiting the spread of fire and smoke in a structure is to subdivide the interior of the structure into compartments using fire walls and fire barrier walls and rated floor/ce iling assemblies . The addition of fire compartments to a building or structure is expected to de lay the spread of fire from th e room or area of fire origin to oth er parts of the structure only if th e compartments are cons tructed and maintained properly and if the openings in them are properly protected . Fire compartments are formed by fire barri ers (this includes fire walls and fire barrier walls and horizonta l fire-resistance rated assemblies) that are both vertically and horizonta lly continuous. This continuity ensures that the compartment where the fire originates will limit , if not prev ent, th e spread of fire and smoke into adjacent spaces. Properly maintained opening protectives in fire walls and fire barrier walls (see NFPA 101 ®, Lif e Safety Code ®, NFPA 5000, Building Construction and Safety Code, and NFPA 221, Standard for Hig h Chall enge Fire Walls , Fire Walls, and Fire Barrier Walls) is essent ial to contain a fire unti l automatic or manua l fire suppression is effective and ensures that the continuity of the fire barriers has not been brok en. Part of the inspect or's responsib ility, th erefore, is to determine th at these openings rem ain properly protected and that nothing has been done to null ify or defeat their prot ec tion. Several Nati ona l Fire Protection Association (NFPA) documents provide requirements for the inspection, testing , and maint enanc e of particu lar opening protectives . The inspector's responsibility is also to be aware of where these requir eme nt s are located and how and when they are applied. A variety of ope ning protectives in fire walls and fire barrier walls is available. The method selected will depend on th e type, function, and configuration of the open ing . Typical protection methods includ e firestopp ing, fire-resistive construction , fire-protection rated doors, fire dampers, and fire-rated glazing materia ls, although special probl ems ma y require other forms of protection . Fire walls are intended to retain their structural int egrity and remain stab le in th e event of bui lding collapse as th e result of an un contro lled fire on either side of th e wall. Fire barri er walls rely on the building

CHAPTER1 O:Protection of Openings in FireRated Assemblies

framing for structural stability. See Ch apter 7, Building Construction Element s, for additional information on the detail s of fire barriers, fire barrier walls, and fire walls.

HORIZO N AL OPENINGS If left unpro tec ted, opening s in fire walls and fire barri er walls, referred to as Jwrizo11/n/ openings, will p ermit fire to spr ead in the horizon tal dir ection throughout the floor of or igin. For exampl e, opening s in fire-resi stan ce rated corridors mu st be protected, not on l)' because the}' are a path for the ho rizon tal spread of fire, smoke, and toxic gases, but also because thq are a part of the means of egress through which the occupa n ts must pass in order to exit the buildin g. Minimi zing fire and smo ke movemen t from a room of orig in to a corrido r is, therefore, an impo rtan t goal of the barr ier as well as the opening protective feature .

Fire Door Assemblies One of the most wide!}' used open ing protectives in fire-res istan ce rate d walls is the fire door assembly. (Fire barrier walls and fire walls are given a fire-resistance rating, wher eas ope n in g protectives are given a fire-pro tect ion rating). Fire-protection rated door assemb lies are tested in accordance with NFPA 252, Standard Metliods of Fire Tests of Door Assemblies,also comm only known as Am erican Society for Testing and Materials (ASTM) E 2074, Stn,1dnrdTestMethodfor FireTestsof DoorAssemblies,IncludingPositive ging Door Assemblies. Such assembli es Pressure Testi11gof Side-Hinged and Pil'otedSwi11 must be installed in accordance with the requi rem ent s of NFPA 80, Standardfor Fire Doorsn11dOther OpeningProtectives.Tests conducted by independ ent testing laborato ries in accordance with these accepted test methods determine the fire-protection rating of a fire door assembl)'- Fire door assemblies are given an hourly rating designation based on the duration of the fire test exposu re for which the door has bee n tested. l11e requir ed houri}' fire-protection rating is based on th e required hourly fire-resistan ce 10-1. rating of the component in whi ch th e assembli es are located , as illustrated in TABLE Fire doors must be identified by a label. Labels on fire doors must be maintained in legible condition. Lab els or classification marks may be of metal, paper, or plast ic or th e)' may be stamped or die-cas_t into the item. Very large fire doors may not have a listing mark if they exceed the size of the door the testing labora tory can physically test. How ever, the laboratory may furni sh the do or with a certifica te of inspection that states that it conforms to the same requir ement s of design , materials, and construction as a rat ed fire door, even thoug h it has not been subjected to an actua l test. If the label on an existing fire door has been removed or is no longe r legible, it is acceptable to verify the ratin g of the fire door through other mean s accept able to the au tho rity having jur isdiction (AHJ), such as an inspection or certificat ion service that provides acceptable docum entat ion. Ratings, Each fire door classification has specific appli cat ions. One war to class ify fire-pro tec tion rated doors is by the ir hourly rating. For example, where a fire wall is provided to sepa rat e two buildings or divide a building into two fire compartments, th e use of a 3-hour fire door assembly is requ ired. In indust rial and storage buildings that

113

1,1\

m

t"'I

Minimum Fire Protection Rating s for Opening Protectives in Fire Resistance-Rated Assemblies and Fire-Rated Glazing Markings

::! 0

z IJ

Component Elevator ho,srways

Elevator Lobby (per

Wall s and Partitions (hr)

Fire Door Assem blie s (hr)

Door Vi sion Panel Maximum Size {in2}"

Fire -Rated Glazing Marking Door Vision Panel

Minimum Side Light / Transom Assemb ly Rating (hr)

Fire Protection

Fire Resistanc e

Fire-Ra t ed Glazing Markin g Side ight/ Tran som Pane l

Fire Protection

Fire Resistance

Fire Window Assembliesb , c

(hr)

Fire-Rated Glazing Marking Window

2

1/.:-

1551n) d

D-H-90or D-H-W-90

NP

2

NP

D-H-W-120

NP W-120

1

1

155in,2d

D-H·60or D·H·W-60

NP

1

NP

D-H-W-60

NP W-60

'h

yj

85 in.2,_.

D-20or D-W-20

½

v.,

D-H-20

D-W-20

NP W-30

I

1

100 in.~b

,:;l00 in. ], D·H•T•60or D-H-W-60->

NP

1

NP

D-H-W-60

NP W.«!

D·H·W-120

NP W-120

D·H•W-60

NP W-60

O-W-20

NP W-30

7.2.13.4)

>100in. •, D-H-W-6QO Vertical shafts, including stairways, exits. and refuse chutes

2

1½

MaximJm size tested

D-H·90 or D-H-W-90

NP

2

NP

1

1

MaximJm size ested

O·H-60-:ir u- H-W-60

p

1

p

Replacement panels In existing vertical shafts

1/,

Y,

Maxim um size tested

D·20o r D-W-20

Y.,

~J

O·H-20

Fire barriers

3

3

100in,2b

s 100 In. 2,0 -H180or D-H-W- l SQh

NP

3

NP

0-H-W-180

NP

W-180

NP

W-120

>100 in. 2, D- H-W-lS()h

2

V,

1½

Maximum size tested

D-H-90or D-H-W-90

NP

2

NP

D-H-W-120

1

·1/.t

Maximum size testedf

0 -H-45 or D·H·W-45

-)(,f

¾i

O-H-45

O-H·W-45

~l.1

v,

1/,

Maximum size tested

D-20 or D-W-20

Y,

Y,

D-H-20

0-W-20

Y,

OH-20or W-30

Horizaf'\tafexits

2

11/,

Max,mum size tested

D-H-90 or D·H·W-90

NP

NP

D-H-W-120

NP

W-120

Horizantal exits served by bridges betweer1 buildings

2

-)(,

Maximum size testedi

D·H-45 or D-H-W-45

~~f

,;.,f

D-H-45

D-H-W-45

%

OH-45 or W-120

Exit access corrido rs9

1

1/,

Maximum size tested

0-20 or D-W-20

¾

¾

D-H-45

D·H•W-20

¾

OH-45 or W-60

'

v,

Maximu m size tested

D-20 or D-W-20

Y,

1/,

D-H-20

D-H·W-20

v,

OH-20 or W-30

Smoke barriers•

1

1/J

Maximum size tested

D-20 or D-W-20

~4

-!~

D-H-45

D-H-W-20

J/4

OH-45 or W-60

Smoke partitionsQ.h

½

v,

Maximum size tested

D-20 or D-W-20

Y,

½

D-H-20

D·H·W-20

V,

OH-20or W-30

OH-45or W-60

NP:Not permnted. 0 Note: 1 1 nch2 ~ .000645I 6 m2. bFirereslstilnce -rated glazing tes ed to ASTME 119.SrondordTm Merhodsfor F1tcTesrsof Bui/dingConsrruct,oncndMaterials.or ANSINL 60, Standardiar FireTl>s tsof Buitd,ngConmucr,on and Moter,ats.shall be permittedIn the maximumsizetested.lsee8.3.3.1.) cF1re -rated glaz,ngIn exteriorwindowsshallbe markedIn accordanceWithTable8.3.3.12. o~ ASMEA17.1.SafetyCode for Elevato/5 and Escalalor s.for additionalInformation. OSeeASTMA17.3,Safety Codefor ExistingElevatorsand Escalators . for additionalinformation. 'Maximum areJof Individualexposedlightsshallbe 1296in.1(0.84m2) with no dimensionexceeding54 In.(1.37m) unlesso herwlserested[80:Table4.4.5,Noteb,and 80:4.4.S.1 J 9Firedoors arenot required co have a hose streamtest per NFPA252, StandardMe/hodsof FireTesrs of DoorAssemblies; ASTME2074.Standard TestMerhod for F1teTemof Door Assembhes.tncludingPos,t,ve Pressure TesNng of Side-Hinged and PivotedSw,ng,ngDoorlmembJres;ANSI/ULl OB.Standardior FireTcmof DoorAssemblies; or ANSVUL1OC:.Standardfor PositivePressure F,reTestsof DoorAssemblies. hForresidential boardand care.see32.2.3.1and 33.2.3.1.

::,

SECTION2: Building Systems and Fire Protection Systems

have vehicle openings, two fire doors are normally required for reliability of closure and are mandated by NFPA 221 on 4-hour rated fire walls. Openings in double fire walls should have one fire door in each separate wall or two fire doors in a freestanding fire-resistive vestibule (FIGURE 10·1). If the corridor is provided as a smoke barrier only, a 20-minute rated fire door is acceptable. NFPA 101® and NFPA 5000 require that hazardous areas be separated from all adjacent areas in a building by 1-hour fire barriers as one method for protecting the hazardous area. Openings in these fire barrier walls enclosing hazardous areas also can be protected with fire door assemblies, whose rating would depend on the fire-resistance rating of the walls. Depending on the 1.ocal codes or ordinances in effect, the fire-resistance rating required for a specific app lication may vary. Doors in openings in exterior walls that might be subjected to severe fire exposure from outside the building as well as doors protecting openings in 2-hour enclosures of vertical building openings ar e required to have a l ½-hour fire-protection rating. One hour rated stair enclo sures are protected by 1-hour fire door s. Rated ¾-hour fire door assemblies are used to protect openings in the exterior walls of buildings that might be subjected to a light or moderate fire exposure from outside the building. Rated ¾-hour fire door assemblies are used in some room -to -corridor openings, especially to isolate a hazardous area from the corridor. Fire door assemblies with ½-hour and 20-minute fire-protection ratings are intended primarily for limiting or controlling the passage of smoke. TI1ese doors are used across corridors in which a smoke barrier is required and to protect openings in walls with fire-resistance ratings of up to 1 hour that are installed between a room that could be occupied and a corridor.

1 layer of building paper between vest ibule mantel and wall mantel

Roll-up fire doors Fire door guide rails

FIGURE 10-1Doub le fire walls wit h one fire door in each separate wall or two fire doors in a NFPA 221,2012. freestanding fire-resistive vestibule. Source: 116

CHAP ER 10: Protection of Openings in Fire Rated Assemblies

Because many inspectors will be working with exis ting fire doo rs, it is also necessar)' to recognize the classificatio n of fire doors by an alphabet ical letter scheme, which at one time was one of the methods used to classify the opening for which th e fire door is considered sui table. From NFPA 80, Annex D, the relationship between the alphabetica l designation and its use is as follows: l.

2. 3. 4. 5.

Class A: Openings in fire walls and in walls that divide a single building into fire areas. Class B: Openings in enclosures of vertical communications through buildings and in 2-hour rated par titio ns providing horizonta l fire separat ions. Class C: Open ings in walls or partitions between rooms an d corridors havin g a fire resistanc e ratin g of 1 hour or less. Class D: Openings in exter ior walls subject lo severe fire exposure from outside the bu ilding . Class E: Openings in exterior walls subject to mode rate or light fire exposure from o utside the building.

Construction. Severa l types of construction are used in the manufacture of fire doors. See NFPA 80, Annex G, for additional details. Compos ite door s are flush doors made of a manufactured core material with chemicall}' impregnated wood edge banding. They are faced with untreated wood veneer or laminated plastic or they are encased in steel. Hollow metal doors are made in flush and panel designs of 20-gauge (0.036 in., or 0.9 mm) or heavier steel. J\'1etal-clad doors are flush or panel-design swinging doors with metal -covered wood cores or stiles and mils ,md insulated panels cove red with 24-gauge (0.024 in., or 0.6 mm) or lighter steei. Sheet metal doo rs are made in cor rug ated, flush, or panel designs of22-gauge (0.028 in., or 0.7 mm) steel or lighter, and 10·2). rolling steel door s are fabricated of interlocking steel slats or plate stee l (FIGURE Meta l- or tin -clad doors are of two - or three -ply wood core construction . They are covered with 30-gauge galvanized steel plate or terne plate with a max.imum size of 14 by 20 in. (356 by 508 mm) or wilh 24-gaug e (0.024 in., or 0.6 mm) galvanized steel sheets with a maximum width of 48 in. (1220 mm). Curtain -type doors consist of interlocking steel blades or a continuous formed -spring steel curta in installed in a steel frame. \-\'ood core doors consist of wood, hardboard, or plastic face sheets bonded to a wood block or a wood particleboard core material with untreated wood edges. Special-purpose fire door assemblies called horizontal sliding accordion or folding doors also are available. They are self- or au tomat ic-closing doors, and some of them are power operated . Under some codes, folding doors are permitted within a means of egress as horizontal exits or in smoke barriers under certain restriclions, such as the provision of backup power for power-operated doors. Materials used in these types of doors vary. Door Closing. Fire do ors must be self-closing or close automa tically in the event of fire. A suitable door hold er/re lease device can be used, provided the automatic rele ase feature is actuated by automatic fire detection devices. Power-operated fire doors must be equipped with a releasing device that shall au tomatically disconnect the power operator at the time of fire, allowing the door to become self-closing or automatically closing. Generally, automatic release that is accomplished with fusibl e

117

0:,

Face of wall mount

Fire-resistive or noncombustible construction

-v

Curtain Hood Bottom bar Note: Drop lever arrangements can vary with different manufacturers.

Guide-

Expansion clearance· Floor ~

/ / / / // S ingle Doo r

ELEVA TI ON

Wall bolt

PLAN S ECTI O N (Sin g le Doo r)

_J

-a / /. __.,_.._ ...-+-' ~/-t Do uble Doo r

• Expans ion clearance per door listing. Doors with downward expans ion are as shown . Doors with upward expans ion requi re expansion clearance above the top of the door. Note: Fusible links are needed on both sides of the wall-configurat ion could vary.

FIGURE10-2 Rolling steel doors:surfacemounted. Source: NFPA 80,2010.

0

:

Guide Bottom bar

J

~ PLA N SECTI O N (Double Doo r)

Wall bolt for masonry constr uction: Through-bolt. or expans ion anchor. as permitted by door listing . Wall bolt for nonmason ry wall construction: Through-bolt, or machine sc rew into steel jamb . or lag screw into wood ja mb, as permitted by door listing .

CHAPTER1 O:Proceclion of Openings in Fire RatedAssemblies

links is permitted only in limited areas. NFPA 101® permits door leaves in the means of egress of buildings with low or ordinary conten ts, or where permitted b)' the AHJ, to be held open by an automatic releasing device. TI1e triggering of the automatic release is done through the operation of smoke detectors installed in accordance with the requirement s for smoke detectors for door release service as specified in NFPA 72®, Nntio11nlFireAlnr111mui Sig11n/i 11 g Code. Fusible links are not an acceptable trigger in this S)'Stem, because untenable smoke condition s could easily render an exit enclosure or adjoining fire compartme nt unusable long before the temperature in the vicinity of the door opening has r isen enough to operate the fusible link. Tfthere is any significant distance in elevation between the top of the opening and the underside of the ceiling or rooi: fire detection devices used to ncluate the doo r should be located near the top of the opening and the underside of the ceiling or roof Some types of automatic-closing fire doors are sometimes required to begin closing not more than 10 seconds after the release device has actuated. ·where applicable, this should he verified, becau ea door holder/release device with an excessive time-delay feature could allow a large volume of smoke to pass through the opening before the door closes. Maintenance and Inspection. Added to the standard in the 2007 edition, NFPA 80 requires all fire doors to be inspected and tested at least annually. TI1istest and inspection frequency is applicable to all new and existing fire door installations. A written record of the inspection is required to be signed and kept for inspection by the AHJ. ·n1ree parties have an important role in the fire door inspection process: the building owner/property manager, the fire door inspector, ,md the AHJ. The building owner must ensure tha t the fire door inspect ions are scheduled and completed according to the annual inspection requirement. TI1ebuilding owner is responsible for maintaining the records of the inspections for review by the AHJ. Fire door inspectors must have the knowledge and understanding of the opera ting components of the fire door being tested. TI1efire door inspector must also be aware of the minimum testing and inspection requirem ents prescribed by NFPA 80. TI1eAHJ must be aware of the inspection, testing, and maintenance requirements as prescribed by NFPA 80 and must enforce the annual inspection requi rements. TI1eAHJ is responsible for verif)'ing that buildings are up to dale on their fire door inspections and for ensuring that inspections are performed by someone with an acceptable level of knowledge of the fire door assembly. Two parts are required for the annual inspection of fire doors: a visual inspection and a functional test. For swinging fire doors, at a minimu m, the following items must be verified during the visual test:

l. 2.

No open holes or breaks exist in surfaces of either the door or frame. Glazing, vision light frames, and glazing beads are intact and securely fastened in place, if so equipped. 3. TI1e doo r, frame, hinges, hardware, and noncombustible threshold are secured, aligned, and in working order with no visible signs of damage. 4. No parts are missing or broken. 5. Door cle11rancesat the door edge to the frame, on the pull side of the door, do not exceed clearances listed in NFPA 80. 119

SECTION 2: Building Systems and FirePmtection Systems

6.

1l1e self-closing device is operational; that is, the active door completely closes when operated from the full open position. 7. If a coordinator is installed, the inactive leaf closes before the active leaf. 8. Latching hardware operates and secures the door when it is in the closed position. 9. Auxiliary hardware items that interfere with or prohibit operation are not i11stalledon the door or frame. 10. No field modifications to the door assembly have been perform ed that void the label. l J. Gaskets and edge seals, where requir ed, are inspected lo verify their presence and integrity. the For hor izontally sliding, vert ically sliding, and rolling fire door s, at a mi11ina1111, following items must be verified dur ing the visual inspection: I. 2. 3. 4. 5. 6. 7. 8. 9. 10. I I.

12.

13.

No open holes or breaks exist in surfaces of either the door or frame. Slats, endlocks , bottom bar, guide assemb l}', curtain entry hood, and flame baffle are correctly installed and intact. Glazing, vision light frames, and glazing beads are intact and sewrely fastened in place, if so equipped . Curtain, barrel, and guides are aligned , level, plumb, and true. Expansion clearance is maintained in accordance with the manufacturer's listing. Drop release arms and weights are not blocked or wedged. Mounting and assembly bolts are intact and secured. Attachment to jambs are with bolts, expans ion anchors, or as otherwise required by the listing. Smoke detectors, if equ ipped, are installed and operational. No parts are missing or broken. Fusible links, if equipped, are in the location; chain/cable, S-hooks, eyes, and so forth, are in good condition (i.e., no kinked or pinched cable, no twisted or inflexible chain); and links are not pain ted or coated with dust or grease. Auxiliary hardw are items that interfere with or prohibit operation are not instal led on the door or frame. No field modifi catio ns to the door assembly have been perform ed that void the label.

After the visual inspection , a functional test is done to verify that the door operates properly. 1l1is includes verifying operational functions such as door swing, closing, latching, and prope r operation of all closing devices. For sliding doors , the inspector should check the automatic -closing mechanism by lifting the counterbalance weight or dropping the suspended weight. \1\lhen door closers are equipped with a fusible link, the test may be limited to general observation of the device; however, if spare links are available, a preferred test method is to fuse it using an electric heat gun . It is also important to ensure that the link is exposed so heat can reach it. Rolling steel doors should be tested when an opening is not in use and reset only by qualified personnel so that any malfunction that might occur will not interfere with the normal activities on the premises. Vertical guides for rolling steel fire doo rs should be bolted to the 120

CHAPTER1O: Protection of Openingsin FireRated Assemblies

framing through slotted holes to allow for expansion during fire exposure. Likewise,a gap should be provided between the bottom of the guides and the floor. Metal- or tin-clad doors have some special features that require attention. Inspectors should make sure that the door has proper lap over the opening. TI1e binders are sometimes filled with blocking to make the door easier to open. TI1eseblocks must be removed. The door should have chafing strips, which help maintain its fire resistance. Inspectors should note the condition of the door. 1sthe metal covering corroded, torn, or battered? Is there evidence of dry rot? Indications of dry rot include edges caving in and screws pulling out. Tapping the door with a weighted object such as a hammer can give some indication of the extent of the rot damage. Inspectors .~hould make sure that fire doors are not obstructed or blocked in any way or intentionally wedged open so that proper closing is not possible (FIGURE 10·3). Should they find that fire doors have been intentionally blocked or wedged, they should determin e the reason for it and take appropriate action. Where doors have

FIGURE 10-3Fire door wedged open.

121

SECTION 2: lluil ding Systems and Fire Protection Systems

been fastened open to improve ventilation, other ventilating means should be provided . Guards or railings should be provided where necessary to prevent damage from materials-handling equipment. Doing so also discourages employees from piling stock against or near the door. Inspectors should ensure that the movement of balance weight s is free and unobstructed and that fusible links are of the proper temperature rating. They should also verify that fusible links have not been made inoperative by paint, corrosion, or other external conditions . For example, they may have wires that would prevent closure, even if the links did activate, rendering the elements inoperative . Self-closing device s must be kept in work ing condition at all times . Swinging doors normally held in the open position and equipped with automatic-closing devices are to be op erated at frequ ent interva ls to ensur e opera tion , and resetting of the release mechanism shall be done in accordance with the manufacturer's instructions. A sepa rate written record of the tests to the closing device must be maintained and made available to the AHJ in addition to the testing and inspect ion record for the inspection and ope ration of the door itself. When conducting th e annual test for operation and full closure, rolling steel fire doors are to be drop tested twice . ·n,e first test is to check for operation and full closure. A second test is done to verify that the automati c-closing device has been properly reset. Fusible links or other heat-actuat ed devices and release devices should not be painted, and paint shall be prevented from accumulating on any movab le part. In addition to the annual inspection and testing requirement for fire doors, other routine maintenance issues may occur throughout the life span of the door. Any repairs that may need to be made to the door should be identified and completed in an expedi ent manner without delay. \•Vhere it may be necessary lo replace fire doors, hardware, and closing mechanisms, replacements are to be installed in accordance with NFPA 80 for new installations. In the case where a modification to a fully functional and compliant fire door is desired, the laboratory with which the original product or component being modified is listed must be contacted and prov ided with a description of the desired modification . If that laboratory determines that the modifications will not compromise the integrity and fire-resistance capabilities of the fire door assembly, then the modifications are permitted . If the laboratory determines that the desired modifications will compromise the integrity of the fire doo r, then a field visit from the laboratory will be necessary in order to comple te the modification.

Fire Shutters Fire shutters are often used to protect op ening s in exte rior walls. If the potential fire exposure from outside the build ing is severe, shutters rated for l ½-hours are used. \-\There the potential fire exposure is moderate or light , shutters rated for %-hour are used . If fire shutters are installed on the outside of the opening, they should be protected against the weather to ensure proper operation. Shutters must be equipped to close automatically in case of fire. TI1esedevices should not be overlooked on the inspection tour . Like fire doors, where it is necessary, shutter replacements have to meet the requirements for new installations 122

CHAPTER1O: Protection of Openings in FireRated A semblies

and be installed as required by NFPA 80. Fire shutters are to be inspected at the same frequencr as swinging, sliding, and rolling fire doors. Although fire shutters are no longer used lo any great extent in new construction, they are still found on older structures.

Fire Win do w s and Vision Panels Fire window assemblies are designed to protect openings in corridors, rooms, and exterior walls where the potent ial exposure is moderate or light. Some fire window assemblies are Ct]uipped with autornat ic closing devices that are actuated by automatic fire detection equipment. \1\lhen inspecting fire window assemblies, inspectors should be sure the closing devices are in opera ting condition. \!\' ired glass of¼ in.(6111111) thickness and labeled for fire-protection purposes is permitted to be used in approved opening protectives, if the maximum size specified b)' the !isling is not exceeded. Wired glass was frequent!)' used as a vision panel in smoke-stop barriers and in fire door assemblies that protect stairway enclosures (FIGURE 10·4). Other glazing materials that have been tested and labeled to indicate the type of opening to be protected for tire-protection purposes are permill ed to be used in approved opening protectives in accordance with their listing, and for the maximum sizes tested. See NFPA JOJ® for additional permissions for the use of wired glass. NFPA 80 now requires that onl)' labeled fire-protection rated or fire-resistance rated glazing material be used in fire door assemblieswhen perm itted by the door listing. Glazing material in fire windows is to be either fire-protection rated or tire-resistance rated and also must be labeled. It is no longer permissible by NFPA 80 to use wired glass for new installations. Fire-protection

FIGURE 10·4Visionpanel in a fire door.

123

SECTION 2: Building System s and Fire Prot ect io n System s

rated glazing is glazing that has a fire-pro tection rating, indicating it has been tested to th e criteria ofNFPA 257, Standard on Fire Test for Window and Glass Block Assemblies. Glazing that can prove to pass the test criteria for NFPA 251, Standard Methods of Tests of Fire Resistan ce of Building Construction and Materials, is given a fire-res istance rating like that of a wall exposed to the same test criteria. The acceptance criteria for fireprotecti on rated assemblies, such as fire doors, differ from those for fire-resistance rated construction, such as a wall or floo r/ce iling assemb ly. A multitude of glazing products have entered the field over th e past decade, including many products that are capable of passing the criteria of NFPA 251. These products are permitted in applications where a solid wall would be used. NFPA 80 continues to update its requirements to reflect the curr ent industry practic e. Insp ectors should be aware of the existing and new instal lation and maintenanc e requirements for glazing mat erials and be able to identify the various types of glazing that are installed and their permitted uses.

Sills In buildings with nonc om bu stible floo r construction, sills should also be constructed of nonco mbu stibl e mat erials. Special sill construction is n ot requir ed, provid ed th at the floo r structure is extend ed through the door opening . Prior to the 2007 edition, NFPA 80 listed the clearance requirements under the bott om of a fire door based on the pres ence of floor covering and sills. Currently, NFPA 80 limits the maximum cleara nce und er the b ottom of all fire doors to ¾ in. (1.9 cm) . Co mbu stible floo r coverings may extend und er do or openings requir ed to be protected by ½-hour or 20-minute firerated assembli es. Combustible floo r cove rin gs are also permitted to extend throu gh ope nin gs req uired to be protected by 1½-h our, 1-h ou r, or ¾- hour rated fire-protec tion fire doo r assemb lies without a sill where th ey have a minimum critica l radiant flux of 0.22 W I cm2 in accordance with NFPA 253, Standard Method of Testfor Critical Radi an t Flux of Floor Cove ring Systems Using a Radiant Heat Energy Source . Unprotected opening s in floors and ceilings, referred to as ver tical openi ng s, may permit th e sprea d of fire from one floor to another. Esca lators , moving walks, exp ansion and seismic joints, vertical exit stairs , chute s, elevators, shaft s, and atria are all exampl es of vertic al ope nings found in buildings.

VERTICAL OPENINGS Floor/Ceiling

Penetrations

Unsealed gaps, crea ted when holes are made th ro ugh floor/ce ilin g assemblies for routin g cab les, co nduit s, or pipes, permit th e pa ssage of fire, heat and smoke from floo r to floor. On e m eth od us ed to sea l these gaps inv olves m od ular devices th at are sized for the pipe, conduit , or cab le and that conta in an organ ic compo und that expa nd s when heated to sea l th e penetration. Other m ethods of sea lin g suc h penetr ation s includ e th e use of foamed -in -place fir e-resistant elas tomer s, var ious ca ulk in g materials, and poured - or trowe led -in -plac e compo und s. In addi tion, there are bags of fire -res istant material that can be placed around penetrating pipes, cab les, or 124

CHAPTER 10: Protectio n of Openings in Fire Rated Assemb lies

conduits. When exposed to fire, these bags expand and fuse to prevent the passage of the fire products. When plastic pipes or conduits penetrate a fire subdivision, they will melt and create a large opening. In some cases, noncombustible piping can be used at the transition point where the piping penetrates the subdividing wall. In other cases, special penetration seals, such as in tumescent types, are needed that will expand as the result of fire exposure and will fill the void. Many of these materials have been tested and listed or approved , and all can provide the required protection if they are properly installed and maintained. The penetrating object(s) should be supported well enough to keep them from placing any mechanical stress on the seal that could pull the sealant from the opening. Where "temporary" routing of utilities or control cables is a fairly common occurrence, workers tend to neglect to seal the gaps (FIGURE 10-5). The inspector should be alert for such conditions. Often, utility lines are hidden in closets or above drop ceilings and are not obvious during a casual visual inspection. The locations of these concealed, but accessible, fire barrier penetrations should be noted so that they are not overlooked during the inspection process. Over the life of a building, it is important to maintain the integrity of barriers to protect against fire penetration and spread. Renovations or any changes to building utilities will tend to violate the desired compartmentation rules when a building is first occupied; th erefore, vigilance is in order to ensure that all such penetrations are identified and properly protected. One source of information on tested materials, devices , and systems for protecting through -penetrations of fire-resistance rated barri ers that inspectors may use is Volume 2

FIGURE 10-SPipe penet ration through fire wa ll wit h no penetration sealant.

125

SECTION 2: Build ing Systems and Fire Protect ion Systems

of the Underwriters Laboratories (UL) Fire Resistan ce Dir ectory . Thes e devices and systems are designed to resist the spread of fire through openings in fire-resistance rated floor or wall barriers that can accommodate penetrating items, such as electrical cables, cable trays, conduits, and pipes. UL classifies such devices and systems with respect to installation in a wall only, in sta llation in a floor only, or installation in a wa ll or floor. The basic standard used by UL to investigate products in this category is American National Standards Institute (ANSI) /UL 1479, Standard for Fire Tests of Throug h-Penetration Firestops, which is simi lar to ASTM E 814, Standard Test Method for Fire Tests of Through-Penetration Fire Stops.

Stair Enclosures, Shafts, and Chutes Certain vertica l openings cannot be sealed becau se their purpose requires them to communicate between floors . Examp les include stair enclosures, elevator shafts, utility shafts, and chutes for mail, laundry, or trash. Such openings should be enclosed in fireresistive construction . Openings in the wa lls of utility shafts shou ld be protect ed with self-closing fire -protection rated doors approved or list ed for th e purp ose. Op ening s in the walls of stair enclosures and elevator shafts mu st be protected by fire-protection rated self-closing or automatic-closing fire do or assemblie s. NFPA 101® contains strict provisions for what can and cannot open or p en etrat e int o an exit stair enclosure. These strict requirements are there to ensure that the exit stair remain s a prot ected vestibule for occupants to use to safely egress th e building as well as to ensur e that fire starting in th e buildin g does not m ake its way int o th e exit stair encl osure and risk spreading to other floors. This protection also works in the oppo sit e direction by pro viding a sheltered and prot ecte d area for fire fighters to stage and gain access to th e fire floor . The only ope nin gs permitted in the fire barri ers between th e exit and the building spaces are those for entering the exit from any n orma lly occ upied space or corridor and th ose for leaving th e exit to reach th e exit dischar ge. In oth er words, only openin gs provid ed for an occ up ant to ent er and leave th e exit encl osure are permitted . No ope ning th rough the exit enclosure walls-including a door op ening-i s permitt ed from storage rooms, closets, boiler rooms, equipm ent spaces , utilit y rooms, electri cal vaults, or simil ar spaces th at are n ot norm ally occ upied. Penetrations int o, and ope ning s th ro ugh , an exit enclos ure assembly are limit ed to the followi ng: 1.

2. 3. 4. 5. 6. 7. 8. 9.

Permitted door asse mbli es. Electri cal conduit servi ng th e exit en closure. Requir ed exit doo r ope nin gs. Ductwork and equ ipm ent necessary for independent sta ir pressurizati on. Water or steam piping necessary for th e heatin g or coo ling of the exit enclos ur e. Sprinkl er piping . Standp ipes. Existing, prop erly prot ec ted, pene tr ations. Penetrations for fire alarm circuit s, wh ere th e circuit s are inst alled in m etal condu it and the p ene tr ati ons are properly protected.

It is n ot uncommon for occ up ants to prop ope n stair door s for th e sake of convenien ce. Woo d blocks, wedges , or pieces of wir e or rope n ear a fire doo r indi cate that 126

CHAPTER1O:Protectionof Openings in Fire Rated Assemblies

the occupants are blocking or holding the fire door open. This, of course, defeats the purpose of a fire door and is a condition that must be identified by an inspec tor and corrected immediately. If this situa tion become s common and impossible to enforce, you may conside r requiring the installation of magnetic hold -open devices with appropriate actuation devices. NFPA 101® permits the use of magnetic hold -ope n devices in any building of low or ordin.iry hazard contents or where approved by the AHJ. The auto matic releas ing device is activated by a required smok e detector, and upon activation, the door is released and becomes self-closi ng. Doors into and out of stair enclos ures that are fire-p rotection rated must follow the appli cable provisions previou s!)• discussed. The door assemb lies in walls of exit enclosures are to be .I -hour fire-protection rated door assemb lies when used in 1-hour fire-resistanc e rated enclo sures and 1½-hour fireprotection rated door assemblies when used in 2-hour fire-res istance rated enclosures .

Escalators Openings made in floor/ ceiling assembli es to accommodate es alators present a unique protection probl em because enclo sing them in fire-resistive constrnction is not 10·6). practical (FIGURE However, there are alterna tive form s of protec tion. In a fully sprinkle red build o11of Sprinkler Systems, provide s a protection ing, NFPA 13, Standardfor the I11stnllnti scheme for escala tors known as the sprinkler-draft curtain method.

FIGURE 10·6Sprinklers around escalators.Source: NF PA13,2010,A.S13.4 .

127

SECTION2: Building Syste ms and Fire Protec tio n Syste m s

Another method relies 011 a combination of automatic fire or smoke detection equipment , an automatic exhaust system, and an automatic deluge water curtain. Yet another method involves filling the opening with a dense water spray pattern from open, highvelocity water-spray nozzles. The water-spray system is operated automatically by heat or smoke detection and is equipped with manual control valves to minimize water damage. (Details on these systems can be found in the L!feSajety Code Handbook and the Automatic Sprinkler Systems Handbook.) Inspectors should examine the control valves in these systems as they would those in other water -based fire-protection systems to make sure that they are open. One more method is to protect the opening with a partial enclosure of fire-resistive construction in a "kiosk" configuration . 1l1is enclo sure is equipped with self-closing doors. TI1e inspector should check that the doors are in operating condition and that the self-closing feature has not been circumvented in any way. See NFPA 13 for additional details. Duct - and materials-handling systems that penetrate walls, partition s, floors , and ce ilings contrib ute to both the hori zontal and vertic al spr ead of fire.

BIBLIOGRAPHY Cote, A. E., ed ., FireProtectionHandbook, 20th ed., NFPA, Quincy, MA, 2008. Cote, R., and Harrington, G., L!feSafety Code Handbook, 12th ed., NFPA, Quincy, MA, 2011. NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Catalog for availability of current editions of the following documents.

Systems NFPA 13, Standardfor the Installation of Spri11kler NFPA 80, Standardfor FireDoors and Other Opening Protectives NFPA 82, Standardon Inci11emtors and Wasteand Linen Ha11dli11g Systemsand Eqclipme11t NFPA 90A, Standardfor the J11stallatio11 of Air-Conditioningand VentilatingSystems NFPA 90B, Sta11dardfor the Installation of Warm Air Heati11ga11dAir-Co11ditio11i11g Systems NFPA 91, Standardfor Exhaust Systemsfor Air Conveying of Vapors,Gases,Mists, and

Noncombustible ParticulateSolids NFPA 92, Standard for Smoke-Control~)'stems NFPA 101®,L{fe Safety Code® NFPA 105, Recommended Practicefor the lnstallation of Smoke-ControlDoor Assemblies NFPA 221, Standardfor High ClwllengeFire Walls,Fire v\!alls,and FireBarrier Walls NFPA 251, Standard lvfethodsof Tests of Fire Resistanceof Building Construction and

Materials NFPA 252, Standard Methods of Fire Tests o_{DoorAssemblies NFPA 253, Standard Method of Testfor CriticalRadia11tFlux o_{FloorCoveringSystans

Usinga Radiant Heat Energy Socirce NFPA 257, Standardfor Fire Testsof Wi11dowAssemblies NFPA 5000, Building Construction and Safety Code 128

CHAPTER

11 ELECTRICALSYSTEMS JeanJvl.Blanc

Electrical .inspections are a vital publ.ic safety function because they contribute to the saving of property and lives. Electrical systems are examined by qualified electrical inspectors, who have learned the special skills and expertise required to identify and correct electrical system deficiencies that may lead to fires or other hazards. Fire inspec tions are typically carried out more frequently than electrical inspections, however, and it is likely that a fire inspector, rather than an electrical inspector or a qualified electrician, will detect potential problems. 'fl1e fire inspector must be aware of the signs and symptoms of potential fire hazards presented by electrical systems . 1he causes of electrical fires can be placed in four broad categories: damaged electrical equipment, improper use of electrical equipment, accidents, or defective installa tions. Tiie fire inspector can eliminate the various sources of electrical failure that cause fire by .learning to recognize the signs of potential hazards.

WIRING AND APPARATUSHAZARDS Electrical fires are primarily the result of arcing faults and overloads in circuits. Arcing occurs when electrical current flows across gaps in otherwise conductive pathways. TI1ese gaps may be created in the normal operation of equipment, such as in switches or in motors. Spacings may also be created at loose splices and terminals or where wire or conductor insulation has been impaired and is in close proximity to other damaged conductors or grounded metal enclosures or surfaces. Arcing produces enough heat to ignite nearby combustible materials, such as insulation, and can throw off particles of hot metal that can caus e ignition. Arcing is dangerous because it can also melt the insulation off conductors. When electric current passes through the air between ungrounded conductors or between ungrounded conductors and grounded conductors, temperatures can reach up to 35,000°F (19,426°C). Exposure to these extreme temperatures can result in irreversible third -degr ee burns and may have fatal effects. TI1e conditions that create an arc usually cause overcurrent protective devices (such as fuses and circu .it breakers) to trip, making the duration and excess heat exposure

SECTION2: Building Systems and Fire Protection Systems

from a possible blast brief However, intermittent arcing, as may occur due to accidental damage, can arise without tripping circuit breakers or fuses. Special devices, referred to as arc-fault circuit-interrupters (AFCls), are designed to detect such arcing, but they are currently required only to be installed in certain residential and commercial applications. Overheating in compression is more subtle, difficult to detect, and slower to cause ignition, but it is equally capable of causing a fire. Conductors and other electrical equipment may generate a dangerous level of heat when they carry a current in excess of rated amperage. Overloading may cause conductors to overheat to the point at which the temperature is able to ignite nearby combustible materials; overheating is also caused in part by improp er ventilation . Insulation failur e caused by overh eating also can lead to arcing between conductors and adjacent grounded objects.

Common Faults Conduits , Raceways, and Cables . Aside from the faults discussed, other hazards exist in electrical systems, such as deteriorated and improperly supported conduits, raceways, and cables. Where these items enter boxes, cabinets, and other equipment, they should be terminated in proper fittings that hold them securely in place without damaging the conductor insulation. Conduits that are not supported properly may pull apart and expose conductors and insulation to damage. Cables should be protected from mechanical damage where they pass through walls or floors. 1he cables and conductors should also be protected from an overload, which may not be as evident as physical damage to the insulation. 1he proper way to deter mine whether a cable or conductor in a conduit has had an overload condition is by conducting a test or measurement through a device listed and suitable for that purpose. Depending on the load, the cable or conduit may be unsafe to touch; therefore, physi cal contact is not recommended. Many conductors and equipment in normal use may operate at temperatures of up to 1678°F (758°C). Because of these high temperatures, when overheating is suspected during an investigation, the inspection should be fur ther pursued by a qualified person. Infrared scanning equipment is encouraged and also available to make a more objective assessment of actual and relative temperatures in a system. 1his method does not require any physical contact from the inspector, which makes for safer work practices. Circuit Conductors. Single conductors usually are installed in raceways, but they may be installed on insulators in free air or in cable trays. Open conductors are more common in industrial occupancies and in older buildings. Like cables, branch circuit conductors must be supported properly along their length and at the point at which they terminate in junction, switch, and outlet boxes. Conductors should not be exposed to excessive external heat, which will accelerate the deterioration of their insulation. Faults can occur from a hot conductor to a ground conductor (short circuit) or from a neutral to a hot conductor . Circuit conductors also may be subjected to electrical overload where fuses or circuit breakers are of the incorrect value. To detect overloaded conductors , look for discoloration of the terminals or of the surfaces of conduits and boxes. 130

CHAPTER11: Electrical Systems

Flex ible Cords. Several unsafe practice involving flexible cords may result in fires. One of the mosl common unsafe practices is use of Jlexible cords or extension cords in place of what should be the fixed wiring of a building. Extension cords should be used only to connect temporary portable equipmen t, not as part of a permanent wiring method. No r should extension cords be used to supply equipment that will exceed their full-load current rating. Extension cords arc nol required to have the same current carrying capacity as the branch circuit wiring supplying a wail receptacle outlet. Therefore, it is extremely important to ensure that the equipment supplied by the cord has a lower current rating than that of the extension cord. 'TI1 e terminations of the conductors in a flexible cord should nol be relied upon lo provide mechanical support. Rather, cords should be clamped iu a connector or secured in an approved man ncr lo keep stresses from being transferred to the conductor terminals. Flexible cords should never be run where they can be damaged by vehicles, mobile earls, or pedestrian traffic. Nor should they be left coiled or run under rugs or carpets. Extension cords and other Ilexible cords should not be attached to building surfaces, woodwork, pipes, or other equipment or run through doors or windows or through holes in walls, floors, or ceilings. Damaged cords should always be replaced and never repaired or spliced. However, broken or damaged cord ends may be replaced using listed devices. Mishandling and improper use of these cords will result in fines for violating Occupational Safety and Health Administration (OSHA) requirements. There are many legitimate uses for flexible cords. Flexible cords can be used for pendants, for connecting portable appliances or lamps, and for some permanent equipment such as submersible pumps or equipment that must be frequently moved or interchanged. Some devices, such as relocatable power taps (power slrip s), may be attached to building surfaces or furniture, but the cords themselves should not be attached to the building and never used as a substitute for the fixed wiring of a strncture. Boxes and Cabinets. Outlet, switch, and junction boxes as well as cabinets are used to protect the equipment and connections they house while withstanding the sparks, arcs, or hot metal that may be produced in the equipment . All such boxes should be equipped with the proper cover. Boxes and cabinets are made with prepunched concentric and eccentric knockouts that can be removed to allow the installation of cable connectors and the entrance of a cable. On l}' those "knockouts" lhal are necessary to accommodate the conductors entering the box should be removed. All other openings must be closed, including any knockouts that may have been removed in error or that result from modification to an existing installation. T11enumber of wires in a box or cabinet must not exceed the number for which it was originally designed. V\lhenobserving outlet and switch boxes, inspectors should look for physically damaged switch and outlet assemblies, discolored devices, or covers that indicate overheating. If any are located, the}' should be replaced promptly. Lastl}1, as with all electr ical equipment, inspectors must also ensure that the equipment being used has been proper!}' listed, labeled, and is suitable for use. Switchboards and Panelboards . On some switchboards and panelboards, there are exposed live parts from which occupants must be protected (FIGUR E11-1). T11iscan be 131

SECTION2: Building Syste,ns and File Protection Systems

(a)

(b)

FIGURE 11-1(a) Generator panelboard. (b) Panelboard with motor control center (MCC) and smaller panelboardsalong the same wall.

done by placing a cage or barrier around these open switchboards. Such boards usually also use bus bars, which shou ld be adequate ly supported . During the inspection, switchboa rds and panelboards shou ld be examined for deterioration, dir t, moisture, tracking, and poor maintenance. Inspectors should also make sure that the surrounding area is kep t clear to allow qu ick and ready access and prohibits the storage of combustible as well as noncombustible materials. Nothing shou ld be stored in this working space or on top of switchboards or pane lboard s. 1l1e working space is intended to provide an area for personnel to perform any operation or required maintenance without jeopardizing worker safety. NFPA 70E, Stm1dardfor Eleclricnl Safety in the Workplace, covers electrical safety requirements for personnel, focusing on practical safeguards for electrical safety.

132

CHAPTER11: Electrical Systems

Lamps and Luminaires. Luminaires are subject to deterioration and poor maintenance. vVith age, the insu lation on luminair e wires can dry, crack, and fall away, leaving bare or exposed cond uctors. Sockets may become worn and defective, and the lumi naires themselves may loosen in the mountings. l uminaires should not be mounted clirectl>'on combustible ceilings unless specifically listed for that purpose. Lamps often operate at temperatures high enou gh to ignite com busti ble material. They should be mounted far enough away from combustible materials such as paper or cloth , which may be used as window shades or placed nearby, so that their con tinuou s operation does not ignite them. Oversized lamps can cause excessive temperature increas es in luminaires, and th ese co nditions can damag e the supply conductors or ignite nearby com bustibles . ll1e inspector shou ld take care lo ensure that lamps nre of the prop er size and type and that the fiberg lass thermal barrier is in the lmninair e's canopy. Discolored globes or len ses may indicate an improp er lamp size application. Most luminai res are marked with the appropriate lamp types and maximum ratings. Newer, recessed lum in aires have th ermal pro tectors that will de-energize the lumin aires if incorrect lamp sizes result in high temperatures. Unguarded portable lamp s may ignite combusti bles if placed in contact with them, and a broken lamp may ignite combustible dusts in suspension or flammable vapors in the atmosphere. A Ithough halogen lamp elements now come in lower ratings, combustible building materials should be kept away from such luminaires. Because bulbs may be hot, it is not recom mend ed that they be touched, and hands should be kept away from sockets if the inspector is not a qualified person.

Grounding and Bonding Grounding and bonding are essential for mailltaini 11gsafety when dealing with electrical systems . Bonding is done to establish electrical continuity and conductivity to create an effective path for fault current that, in turn , facilitates the operation of the overcurrent prot ective device. Equipment bonding min imizes the differences in electr ical potential behveen metallic objects. For instance, minimal differences exist between hvo metal objects connec ted via an equipment bonding conductor. TI1eequip ment bondi ng conductor is used to dissipate electr ical charges that might otherwise accumulate on equipment and that may lead to the enclosure becoming energized. Furthermore, grounding describes connections made to minimiz e the difference in electrical potential between objects and th e ground and to provide a low-resistance path t. In such cases, the groundi ng conductor ca u carq, th current from power circuits that are much larger than static current. Ground con nectio ns must be exami ned when they are installed and frequently thereafter to de tect corrosion, loose connectio ns, or damaged insulation . Flowing gases, liquids, or granular solids, such as sand, generate static electricity. TI1Us,their containers should be bonded or gro und ed (FIGURE 11-2).When gasoline is transferred from a drum to a can, for example, the drum and the can should be bonded together by an electrically conductive tube that is firmly in contact at both ends or securely attached to a grounding conductor before the liquid is tran sferred. ll1e electrical currents involved in static discharge or stray voltage are quite small, even though th e voltage may be h igh; for that reason, small conductors are adequate

133

SECTION 2: Build ing Systems and ~ire Protection Systems

Building sta tic ground ing "bus" /

r )~

in. stainles s steel grounding cable

%i n.- ----' "'1 slain less steel grounding cable Conn ector

2 in. x 3 in. x ;;. in. gmund ing tab

~

Open pail

#1/0--1/C stranded wire building gmund "bus"

Portable ground ing reel with 20 fl of 5/22 in. diameter stai nless steel cable ratchet latch ing

Standard wall-mounted - ground ing lab

Grounding clamp -

-1--h- 1;11.

Open pall grounding arrangem ent

FIGURE 11-2Recommended meth ods of bondi ng nammab le liquid containers during container

tilling. 134

CHAPTER11: Electrical Systems

to dissipate the voltages. Grounding and bonding conductors and connections should be installed in a manner in which there are not any loose connections and in an area in which there is no potential for frequent mishandling. Installations should be installed in a professional manner so they can be easily verified and inspected.

Grounding Groundi ng facilitates the operation of the overcurrent devices installed in ungrounded conductors. One of the system's condu ctor is grou nded, and all the metal parts that could be energized are connected to it through equipment-groundin g conductors and bonding jumpers. ff a ground fault occurs, this wiIIprovide a path to the grounded system conductor, which will cause the overcurrent device to open. Grounded conductors are usually identified by either a white or gray insulation. Equipment grounding conductors are usually bare or identified by a green finish. Metal cable armor, ra eways, boxe , and fittings, as well a the frame and housings of electrical machinet'}', are required to be grounded . Certain electrical tools and cordand-p lug-conn ected appliances, such as washers, dryers, air-conditioners, pumps, and so on, must be grounded through a third contact in the line plug. A grounding electrode is connected to the system to stabilize the voltage to ground and to limit voltages due to lightning, line surges, or unintentional contact with higher voltage lines. A metallic underground water-piping system must be used as the grounding electrode where it is available and where the buried portion of the pipe is more than 10 ft (3.05 m) long. If a metal underground water pipe is the only ground ing electrode, it must be supplemented by an additional electrode to ensure the integrity of the grounding electrode system. Grounded steel building frames, concrete-encased electrodes installed in footings, grounding rings or grids, and driven grounding rods are other electrodes that may be used. 11,ese may be used either as the main grounding electrode or as a supplement to the water pipe electrode (FIGURE 11-3). Fire sprinkler system piping is prohibited by NFPA 13, Standard for the Installation of Sprinkler S)'stems, and NFPA 24, Stn11dard.forthe Installation of Private Fire Sen 1 ice 1\tfni11s and TheirAppurte11a11ces, from being used as an electrode for grounding of electrical systems in buildings. However, this prohibition does not relieve the NFPA 70®, National Electrical Code®, requirem ent for bonding of metal piping systems in a building. Although sprinkler piping cannot be used for grounding the system, the piping must be connected (bonded) to the system to prevent the piping from becoming a fire or shock hazard if it inadvertently becomes energized. Bonding ensures that a pathway is available that will allow enough curren t to flow to trigger the overcurren t protection device (fuse or circuit breaker) if stray current were to energize the sprinkler piping. Ground clamps and connectors should be checked periodically to ensure that they are tightened and that the ground connection is being maintained. When new electrical machinery or equipment is installed on the premises, it should be inspected to see that it has been connected properly and does not interfere with the grounding system. 135

SECTION 2: Building System s and Fire Prot ect io n System s

Service raceway A = Supply-side bonding jumper B = Load-side bonding jumper C = Main bonding jumper

Meter

Service raceway

Service "LB" conduit body

A

c+- ~~~ Grounding electrode conductor

Feeder

_______.--:,1~-----~

~~L~c Additional supplementa l electrode (can be located elsewhere)

FIGURE 11-3 Grounding at a ty pical small service [alternating cu rrent (AC), singl e-phase, thr ee-w ire, 120/2 40 Y].

Overcurrent Protection Devices Conductors and electrical equipment are provided with overc urrent protection, which ope ns a circuit if the curr ent rating exceeds the maximum temperature ratin g of the conductor. Fuses and circuit br eaker s are the m ost commonly used overcurrent devices for the protecti on of electrical equipment. Thermal overload devices or electronic sensors may be used in conjun ction with circuit breakers and fuses to protect equipm ent such as motors. Plug Fuses. There are two types of plug fuses, the Edison base an d the type S fuse. Both can be eith er of th e quick -ac tin g or th e tim e-delay typ e. The Edison base plug fuse is familiar to most people. Edison base fuses were widely used in older insta llations, but th eir use is now restricted to replacements in exist ing in sta llati ons where there is no eviden ce of overfusin g or tamp erin g. Typ e S fuses m ay be used in n ew installations. The type S plug fuse is designed to prevent th e use of coin s or other bridging schemes to byp ass the fuse and to prevent the use of in cor rect ly sized fuses.

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Cartridge Fuses. Cartridge fuses are made in quick-acting and time-de lay types . They are available for one- time us e or with renewable links. However, the renewab le link cartridge fuses have two drawbacks: two or three links can be installed simultaneous ly, th ereby increasing the fusing current and defeating the purpose of the fuse, and the fuse can be left with loose connections when a link is replaced, which results in overheating . Generally, the two or three fuses installed in a switch wi ll all have the same rat ing. If one fuse has a differe n t rating from the others, this may be an ind ication of overfusing and should be investigated further. Fuses are sometimes replaced by the m ost readily available fuse rather than by the proper size fuse for the application . Circuit Breakers. Circuit breakers are available in a number of styles. The m os t common type has two n onadjustable tr ips, one of which is a thermal trip to detect overloads, and th e other is th e magnetic trip to det ec t short cir cuits. Th ese are called inverse-time or thermal-magnetic circuit breakers . Another type has adjustable trip units, which may have either conventiona l or solid-state sensing units. Some circuit breakers hav e shunt-trip features that allow them to be operated from remote locations. An example is the type of circuit breaker used to shut down equipment und er kitchen hoods in restaurants . Among the special typ es of circuit breakers us ed are motor -opera ted breakers, ground-fau lt sens in g br eake rs, and motor -circuit protectors. Circuit breakers may also include ground-fault circuit-interrupter (GFCI) protection or AFCI protection. Any of these devices ma y feel warm under normal loads, but non e should be too hot to touch. Thermal Overload Devices. These devices are n ot int ended to protect against sh ort circuits. Rather, the y protect against overl oad. Examples are the therma l overload devices included in many small motors, the thermal protectors in recessed luminaires, and the thermal protectors in fluorescent ballasts. Ground-Fault Circuit-Interrupters. These devices detect when the current passes to ground through any path ot h er than the correct path . When this occurs, the GFCI trips almost instantly, stopping all current flow in the circuit. GFCis are extreme ly important for life protection in wet locations. GFCI protection is provided by a special cir cuit breaker located in the pane lboard or by a GFCI receptacle inst alled in the outl et box. Unfo rtun ately, no statistics are available for the actual number oflives saved or injuries prevented by GFCI devices. GFCis are primarily intended to protect people from sh ock hazards; how ever, GFCis are also used to prevent fires caused by faults in "heat tape" used for freeze protection of water piping in mobile home s and manufactured housing. Ground -fault protection of equipment (GFPE) is used for the same purpose in ot h er occupa ncies where pipeline h eating or deicing and snow -melting equipment is installed. GFPE does not provide acceptable shock protection for people; it is int ended on ly to protect equ ipm ent. Arc-Fault Circuit -Interrupters. AFCis are devices that can detect the presence of arcing fau lts on circuits even where the current does not rise to a valu e that will trip the overcurrent device. An AFCI does this through recognition of characteristics unique to arcing and by functioning to de -energize the circuit when an arc fault is detected . They

137

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are int end ed to help prevent fires by disconnecting the circuits where such damag e occurs. The first requirement in NFPA 70® for these devices was effective in 2002 and app lied only to circuits supp lying receptacle outl ets in bedro oms of dwelling units. Now they are required in all 120-V, single-p hase, 15- and 20-A branch circuits supp lying ou tlets insta lled in dwelling unit fami ly rooms, dining rooms, living ro oms, parlors, libr aries, dens, bedrooms, sunrooms, recre ation rooms, closets, and hallways , or simi lar rooms or areas shall be protected by a listed AFCI, combina tion-type, installed to provide protection of the branch circuit.

INDUSTRIAL EQUIPMENT Transformers Dry -type and fluid -filled transform ers are us ed in both industria l and large commer cial occ upanci es. Dry -type transform ers are the most common in n ewer commercial construction , alth ough other types may be encount ered, whereas fluid-filled transformers are m ore comm on in indu strial plants or older bui ldin gs. In most cases, dry-typ e transformer s do n ot require a separate room or vau lt, but th ey mu st be separated from combustible materia ls, and the area in which they are loca ted must be adequately ventilated wi th the correct air circu lation . Oil -filled transformers usuall y are requir ed to be installed in a vault with 3-hour fire rated floo r, walls, doors , ceilings, and sills to contain th e contents of the transformer should the y spill. New transform er fluids, classified as less flammable or nonflammab le, are available. When the se new fluid s are used, the requirem ents for vaults are reduced or eliminated. Some older transformers might contain askar el and will have to be mark ed and eventu ally replaced because of env ironm ental conc erns. Under conditions of full load, transformers opera te at elevated temperatures . Many will be too hot to touch for more than a few seconds . All transformers shou ld be provided with adequate ven tilation , and th e clearance requiremen ts marked on the transformer should be maintained. Obstructions should not be in the way of transformers nor shou ld materia ls be stored nearb y or on top of transform er en closures . Outd oo r pad -m ount ed tr ansfor m ers are to be loca ted in such a way th at lea kin g fluid s will drain away from building s or be co nt ained in an iso late d area. They should be placed so th at th ey do n ot obstruct exits or windows in the even t of tr ansfor m er failure and fire.

Motors Motors and ro tatin g m achin es can cause m echanical injury as well as a shock h azard and should be treated with caution (FIGURE 11-4). Man y m otors start aut omatic ally, so even a motor at rest sh ould be tr eated as though it was in operation. Cau tion shou ld be taken with arcs th at arise wh en a m otor h as a short circuit , as this can ignite n earby combu stible s and cause a fire. Bearing s can over heat if th ey are not prop erly lubri cated , and du st depo sits or accum ulations of textile fibers can pr event heat from diss ipating from th e m oto r. 138

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The inspection of a motor should indicate that there are no combustibles in the i..rnmediate vicinity of the motor or its controls, that the equipment is cleaned properly and maintained, and that it has the proper overcurrent protection (FIGURE 11-5). Motors are designed to operate without overheating under norm al conditions , but they also are designed to operate with a tem perature rise well above ambi ent under normal full-load conditions. A hot casing may indic ate a potential problem and should be examined closely.

Med ium -Voltag e Equipm ent Most of the equipment discussed ear lier can operate on medium-voltage and low-voltage systems. Medium voltage usually is considered to be in excess of 600 V (FIGURE 11·6). Equipment rated as high as I 5,000 V is common in large buildings and in dustrial complexes. Because of th e severe shock hazard associated with this equipment, the inspector must use extreme caution when insp ect ing it.

(a)

HAZARDOUS AREAS Electrical hazardous location (or clas -

(b)

sified)areas are those in which flam ma - FIGURE 11·4(a) Cooling tower motors. (b) Pump ble liquids, gases, combustible dusts, motors with panelboard in background. or readily ignitable fibers or flyings are present in sufficient quantities to represent a fire or exp losion hazard . Special electrical equipment is necessary in these areas. The special equipment is intended to keep the electrical system from becoming a source of ignition for the flammable or combustible atmosphere. This equipment is usually specifically listed or identified for the class, divi sion, and, in Class I and II, for the group of materials or chem icals that creates the classified area. Portable equipment should be listed similar ly or identified for suitable use. Complete definitions of the classes and divisions of hazardous locations and of the wiring methods

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SECTION 2: Building Systems and Fire Protection Systems

FIGURE 11-STypical motor wiring method.

FIGURE 11·6Engineering supervision w ill be req uired to determi ne th e sizing or overload and short -circuit protective devices for motors in excess of 600 V.

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and types of electri cal equ ipn1ent to be used in each are covered in Article 500 of

NFPA 70'll.

Class I, Division1 Class l, Division l locations include areas in which igni table concentrations of flam ma ble gases or vapors exist under norma l conditions; areas in which ignitable conce ntrations of flamm able gases or vapors may exist frequently because of repair or maintenance operations or leakage; and areas in which the breakdown or faulty opera tion of equipment or proce sses may cause the simult aneous failure of electrical equipm ent. Electrical equipment used in thes e locations mu st be the explosiou -proof type or the p urged-and-pressuriz etl l)'Pe approved fur lass l location s.

Class I, Division2 Cla ss I, D ivision 2 locations include areas in which volatile flammab le liquids or flam mable gases, wh ich usuall)' are confined to closed containers or systems that allow them to escape only during accidental ruptur e, breakdow n, or abnormal operation of equ ipment , are handled, processe d, or used. They also includ e areas in which positive mechanical ventilati on usually prevent s the development of ignitabl e conce ntrations of gases or vapors that could become hazardous shou ld the ventilating equ ipme nt fail or opera te abnormall) ', as well as areas adjacent to, but not cut off from , Class r,Division 1 locations to whic h ign itab le concent rations of gases or vapors could be communicated, unless such communication is prevented br adequate positive -pressure ventilatio n from a source of clean air, and effective safeguards against ventilation failure are provided.

Class Il, Division1 These classified locations include areas in which com bustible dust is, or may be, in suspens ion in the air cont inuo usly, intermit tently, or periodical!}' under norm al oper at ing condit ions in large-enough qua ntities to p roduce explosive or ignitable mixtures . Areas in wh ich mechanical failure or abnormal operat ion of equ ipment might result in explosive or ignitable m ixtures and provide a source of ignition th ro ugh simultaneous failure of electrica l equipment are also classified as Class II, Division l, as are areas in which combustible dusts of an electrically conduc tive nature might be present. Class II, Division I locations also include areas in which a buildup of combust ible dust on horizontal surfaces over a 24-hour period exceeds ¼ in . (3.1 mm) .

Class 11,Division2 Tilese classified .location s include areas in which combust ible dust usually is not suspended in the air in quantities sufficient to produce explosive or ignitable mixtures and in which dust accu mulations usually are not sulli.cient to interfere with the normal operatio n of electrical equi pment or other apparatus. They also include areas in which the infrequent malfunction of hand ling or processing equ ipment might result in dust in suspension in the air and in which these dust accu mu lations could be igni ted by 14 1

SECTION 2: Building System s and Fire Prot ect io n System s

the abnormal operat ion or failure of electrica l equipment or other apparatus. Areas in which a buildup of combustib le dust on horizontal surfaces is 1/sin. (3. 1 mm) or less, obscuring the surface co lor of the equipment, are also classified as Class II, Division 2 locations .

Class 111,Division 1 This classified location includ es areas in which easily ignitable fibers or materials producing combustible flyings are handled, manufactured, or used.

Class 111,Division 2 These locations include areas in which easily ignitable fibers are stored or handled, except during the manufacturing process.

Class I, Zones 0, 1, and 2 The zone classification system provides an alternative to the Division 1 and 2 classifications in Class I areas. This classification system provides for some alternate protection m ethod s. The classification of areas must be don e by a qualified registere d prof essional engineer. The area classification should be well doc umented, and the documentation should be readil y available . Zones O and 1 correspond roughly to Divisi on l, and Zone 2 corresponds roughly to Divi sion 2.

STATIC ELECTRICITY Precautions against sparks from static electricity should be taken in locat ions in which flammabl e vapors, gases, or dusts or easily ignit ed mat erials are present. On ly qualified individu als should be allowed to test for static charges in th ese loca tions, as unintended discha rges can ignit e th e hazard ous atm osp here. Meas ur es th at will bring th e h azard of static electricit y und er reason able control are humidific ation, b onding, gro undin g, ionization, conductive floors , or a combination of thes e methods.

Hum id ification Humidity alone is not a comp letely reliable means of elimin ating static charges. To reduce th e danger of static, however, th e relative humidit y sh ould be high. If practical, relative humiditi es sho uld be as high as possible, even up to 75 percent, as long as thi s does not create undue ha rdsh ip. Som e indu str ial operat ion s cannot be performed at humiditi es hi gh enough to miti ga te th e danger of static.

Ionization Ionization is the process of in creas ing the co ndu ctivity of air so that it will conduct static charges away from an area. 142

CHAPTER 11: Electr ical Systems

One ionizati on techniqu e uses th e tendency of static to conc entr ate on th e surfac e of least radius of curvature, such as a sharp point. A metal bar with n eedle points (static comb) or with metallic tinsel rem oves static from m oving sh eet mat erials. An ot her technique uses a so-ca lled electrical neutrali zer, which produ ces an alternating elec tri cal field through which th e electrified sheet material passes. Yet an other technique , used on printing pr esses, uses a flame to ioniz e th e sur roundin g air. Stati c m ay also be ionized by alpha radi ation from a radioactiv e surface. The hazards introduc ed by th ese vari ous techniqu es, as well as th eir respective effectiveness in rem ovin g static charges, mu st b e con sidered.

LIGHTNING PROTECTION The risk of dam age cau sed by lightnin g is very high in so m e areas and low in oth ers. The in cid en ce of lightnin g varie s greatly by geogr aphi c loca tion. For exampl e, light nin g is comm on in Florida , yet rare in Alaska. Lightning risks also vary by th e typ e of constru ction or the use of a buildin g, because som e system s and processes are m ore vuln erable to lightning th an oth ers. For th ese reaso ns, lightning prot ection is usually no t required by local codes. H owever, wh ere requir ed or used, lightni ng pro tection mu st be pro perly installed and m aint ained for fire safety. Lightnin g protecti on system s are installed to provid e an altern ate, nond estru ctive path for lightnin g to follow to th e ear th. Wh en lightnin g follows thi s path , buildin g m aterials are spared th e heat and m echani cal forces th at result wh en th e energy of th e lightnin g stro ke p asses thro ugh a structur e. Any p art of a buildin g th at is likely to be struck , such as chimn eys, ventilat ors, steeples, dorm ers, and oth er proje ctions, sh ould be pro tected. This is done by installing a series of air termin als, down condu ctors, and second ary conduct ors and gro und termin als. Sur ge ar restors also m ay be inst alled to pro tect th e buildin g's electri cal system. Air termin als are installed on th e edges of a buildin g's roof and on its ver tical pro jec tion s and conn ected by condu ctors. Dow n co ndu ctors are used to provi de at least two path s to th e gro und termin als. Metal objects n ear by are bond ed to th e system with secon dary condu ctors, which preve nt damage from sid e flashin g. Bondin g also helps to redu ce th e risk of indu ced voltages in m aterials n ear lightnin g condu ctors. In som e cases, th e m etal fram e of a build ing m ay b e use d as th e dow n condu ctor. In all cases, th e condu ctors mu st be resistant to corros ion and h ave the m echani cal str ength ne cessary to fun ction as intended . Most compo nent s, includ ing air ter min als, down cond uc tors, and conn ecto rs, mu st be listed for the pu rpose (FIGURE 11-7). All of th ese condu ctors are cons tru cted of heavy-ga uge copp er or aluminum to resist corros ion. Lightnin g, acci dental cont act with a high-vo ltage sour ce, and surface leakage du e to condu ctive dirt or m oistur e can cause hazardo us voltages in electri cal distribut ion system s an d equipm ent. If th e affected equipm en t is pe rmitt ed to "floa t" at a dangerous voltage, anyon e who comes in contac t with it and a po in t of differen t po tenti al, such as gro un d, will rece ive a serious, if n ot fatal, shock. Gro und ing of electrica l equi pm ent helps to elimi nate thi s shock hazard. Mater ials th at are used for lightnin g protect ion system s are strongly buil t: They re qui re very littl e m ain tenan ce, so inspectors m ay n ot have to inspec t th ese system s as 143

SECTION 2: Building Systems and Fire Protect ion Systems

G)

Typical air terminal for metal or masonry flat roof

Bonding conductor to purlin

2

Bonding column to ground

FIGURE 11-7Grounding and bonding of lightning down conductors.

frequ ently as th ey do other system s. In fac t, N FPA 780, Standa rd for the Installa tion of Lightn ing Protection Systems, recomm end s inspec tin g th em every 5 yea rs. Wh en th ey are in spec ted, condu ctors should be checke d for excessive corr osion or m echani cal dam age. Down conduct ors n ear the gro und m ay be dam aged by vehicl es, and con nections to gro und termin als m ay be distur be d by m owers or oth er land scapin g too ls. Co nnec tions should be ch ecked thr ough out for tightn ess, and air term in als should be inspecte d to m ake su re th ey are sec ur ed and in place. 144

CHAPTER11: Elecuical Systems

RENEWABL ENERGY ELECT ICAL YS M Solar Photovoltaic Systems The widespread increase in renewable energ}' electrical S}'Slemshas added to the responsibility of the fire or electrical inspector. It is apparent that the benefits of these innovative systems outweigh the potent ial hazards that exist; therefore, the inspector must always be aware of the underlying dangers that may transpire when these systems are nol thoroughly examined by a qualified person. Solar photovoltaic (PV) systems can be composed in multiple arrangement types, so the identification of the system's components, circuits, and connections is essential to understanding the functions and to performing proper inspections (FIGURE 11-8).The PV module units usually consi t of solar cells, optics, an inverter, and other components. PV systems use either an alternating current or direct curre!lt output(s) and may be inter11-9). active, stand-alone, or operate with or without batteries for energy storage (FIGURE Because of the variation of PV modules available, the accepted grounding and bonding methods among PY installers, manufachJrers, and even other inspectors may differ. PY systems and wiring are also exposed to severe weather conditions ranging from wind to snow and polarizing temperatures, which can aflect the grounding

FIGURE 11·8 Perspective on a PVsystem.

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SECTION 2: Building Systems and Fire Protection Systems

FIGURE 11-9Mo dules in landscape orient ation.

and bonding. Inspectors are obligated to identify poor grounding methods through abraded cables or conductors, improper conductors and lugs, and dissimilar metals (copper conductors and aluminum module frame) that come into contact with each other, which lead to corrosion. Appropriate interpretations of both the adopted version ofNFPA 70'El(Article 690) and the applicable product standard(s) must always be used to determine the grounding and bonding requirements.

Small Wind Electric Systems Similar to PY systems, use of wind -driven turbines has increased substantially, and these 11-10); can act as a stand-alone or interconnected power generation system (FIGURE however, wind -powered systems present a much different set of hazards. Windpowered S)'Stems have an increased chance of ignition due to overload and introduce new dangers to qualified individuals and personnel working in elevated confined spaces. NFPA 70® (Article 694) provides the installation requirements for small (an individual turbine rated 100 kW or less) wind electric systems to promote safe use of this renewable energy source with premises wiring systems. Inspectors must ensure that warning signs/labels are visibly located where required. For instance, where terminals of a disconnecting means are capable of being energized in the open position, a warning sign should be mounted or adjacent to the disconnecting means, because this is a shock hazard. Terminals on the line and the load sides may be energized in the open position . A warning label will also be displayed for ungrounded systems. 146

CHAPTER11: E.lewica l Systems

FIGURE 11-lOWind energy is expected to double its production from its current rate in the next 3 years.

A warning label may say: '" 'ARNING ELECTRIC SHOCK HAZA RD. THE DC CONDUCTORS OF THIS PHOTOVOLTAIC SYSTEM ARE UNGROUNDED AND ivIAY BE ENERGIZED .

Electric Vehicles An electric vehicle (EV) is defined as an automotive -type vehicle for on-road use and is primarily pow ered by an electric motor that draws current from a rechargeable storage battery, fuel cell, PY array, or other source of electric current. . Voltages that are used to supply The requirement s for EVs are in 625 ofNFPA 7cfiJ EVs range from 120 to 600 V. Although thi s range is relatively high, the above-normal voltage system is cornplete .ly isolated from the chass is of the vehicle. Some EVs are backed upby a 12-V battery disconnection, and int egrated shutdowns of these vehicles occur in

147

SECTION 2: Build ing Systems and Fire Protect ion Systems

the event of a crash or other catastrophic event. This prevents much of the initi al hazard from ever becoming a major concern to first responders involved with accidents. First respond ers and fire inspectors who will be dealing with emergency operations with EV s are strong ly encouraged to undergo professiona l safety traini ng. This recommendation is a result of the recent influx of these EV sand to comprehend the procedures inv olved with identifying, immobilizing, and disabling EV s. As EV supply equipment becomes a growing part of the U.S. infrastructure, it will prompt new technical issues and questions that fire and life safety inspectors must an ticip ate and be prepared for.

BIBLIOGRAPHY Cote, A. E., ed., Fire Protection Handbook, 20th ed ., NFPA, Quincy, MA, 2008. Electrical Applian ce and Utiliz ation Equipment Directory, Underwriters Laborat ories, Inc., Northbrook, IL (issued annua lly). A listing of the electrica l appliances and devices that have been tested and found to be safe for use. Electrical Construction Materials Dir ectory , Underwriters Laboratorie s, Inc., Northbrook, IL (issued annually) . A directory of tested and listed construction m ateri als such as circuit breakers, wires, transformers, industrial control equipment, electrical service equipment, and fixtur es and fittings. Ha zardous Location Equipm ent Dir ectory, Underwriters Laboratori es, Inc ., North brook , IL (issued annually). A listing of electrical components and equipment that have be en tested and listed for use in hazard ous atmospheres. Sargent, J. S., and Wi lliams, N., NFPA Electrical Insp ection Manual wi th Checklists, NFPA, Quincy, MA, 2010. NFPA Codes, Standards, and Recommended Practices See the latest version of the NFPA Ca talog for availability of curr ent edition s of the following documents .

NFPA 13, Standard for the Installation of Sprinkler Syst ems NFPA 24, Standard for the Inst allation of Privat e Fire Servic e Mains and Their Appur tenances NFPA 70®, National Electrical Code ® NFPA 70B, Recomme nd ed Practic e for Electrical Equipm ent Maint enanc e NFPA 70E, Standard for Elect rical Safety in the Workpla ce N FPA 77, Recommended Pra ctice on Static Electricity NFPA 79, Electrical Standa rd for Industrial Ma chin ery NFPA 496, Standard for Purge d and Pressuri z ed Enclosures for E lectrical Equipm ent NFPA 497, Recomm end ed Practic efo r the Classification of Flammab le Liquids, Gases, or Vapors and of Ha z ardous (Classified) Locations for Electrical Installations in Chemica l Process Ar eas NFPA 499, Recommended Practice for th e Classifica tion of Combustib le Dusts and of Ha z ardous (Classified) Locations for Electrica l Installa tions in Ch emical Process Ar eas NFPA 780, Standard for the Installation of Ligh tning Protection Systems 148

CHAPTER

12 HEATING SYSTEMS Allan B. Fraser

This text is specifically focused on fire and life safety inspections; therefore, it is not an exhaustive inspection checkl ist for all heating systems. It is not concerned with the efficiency, effoctiveness, or desirability of any system, but rather on ly with those items or conditions that have the potential for causing fires or other life-threatening condi tions . Why is this type of inspection important? Isn't it redundant? Haven't building or mechanical inspectors already checked to ensure that the install er insta lled the system properly? 1l1e answer is yes, they probably have, but fire and life safety are important enough to warrant a second inspection on soine items. Call it a good failsafe procedure. In addit ion, as any system of moving parts ages, things malfunction or break . 1l1e vast majority of heating systems, as one would expect by their very name and nature , create veq, hot areas within their systems by burning fossil fuels like oil, gas, and coal. These are fires, albeit in relatively safe and secure enclos ures , and need to be treated as potentia l hazards. Even electric heat will start fires or burn the flesh when people or combustible materia ls get too close. There are a few systems, like geothermal heat pumps, that are high I)' unlikely to be a source of ignition because of their relatively low temperatures, but the electr i.cal pumps and wiring for those systems are still capa ble of causing fires. This chapter is intend ed to provide a fire and life safety inspector with sufficient information about which items, devices, and clearances need to be inspected and how to assess when a qualified contractor or engineer should be consu lted to assess further and/or repair the part( s) in question. It will also address various types of heating systems, heati ng fuels, and the instal lation of heat-pro ducing equipment with particu lar focus on the inspector's role in inspecting the fire and life safety protections that are an important part of the heatin g system. It is not intended to be a comprehensive discussion of the complete installation or inspection requirements for heating systems, but rather of typical requ iremen ts and devices related to these systems that are specifically designed to reduce potential fire and life safety hadrds inh erent to the particular type of S)'Stem.

SECTION2: Building Systemsand FireProtection Systems

BUILDING SIZE Large Buildings Most large buildings use oil or gas in boilers that in turn generate hot water or steam that circulates through pipes to provide heat to the building. 1he pipin g systems connect to various units located throughout the building including, but not limited to, airhandling units, unit heaters, finned tube radiation units, radiators, and even ice- and snow -melting systems. Many, if not most, large buildings have abandoned their heavy oil-fired or coal-fired boiler plants because installing and operati ng the necessary pollution abatement devices have become too expensive. In many cases, the savings between the different fuels simply does not offset the higher installation and operating costs. The spaces that had been used to store coal were much more valuable as rentable space, and in most communities, removing the coal ash became a major cost, as well as an environmenta l problem . Building owners are becoming more acutely aware of their energy costs every day. Both construction codes and business economics now dictate more insulation in the exterior walls, replacing single-pane windows with insulating glass, and covering minimally insulated or noninsulated pipe with energy -saving insulation. Repairing and replacing leaking, noncompatible, and noninsulated chimneys and exhaust flues make sense as well. Boilers and heating units are regularly being replaced with more efficient units so that even less energy escapes up the exhaust stacks. Many of these changes have also resulted in improved fire safety, general building safet)', and building value. For example, the added insulation on pipes and other hot sur faces reduces the transmission of heat to adjacent surfaces, which lessens the likelihood of igniting a building fire. More efficient boilers and heating units have greatly reduced stack temperatures, which have resulted in less chance of chimney, chase, and roof fires. In addition, reduced clearances have added to a building's rentable square footage. Improved passive protection around equipment now required by the codes has also reduced fire risks. Large fuel-fired heating equipment above a certain energy input capacity is often required to be located in rooms separated from other parts of the building by fire-resistive barriers . All of the changes noted above have helped reduce the fire hazard from heating systems in both new buildings and renovated buildings, but problems remain in a large number of existing buildings, as well as in some newer buildings that are not properly inspected and maintained.

Small Buildings Many smaller buildings use packaged equipment, although the same type of systems used in larger buildings may be appropriate as well. These packaged systems, often referred to as unitary equipment, contain an extended combustion chamber, called a heat exchanger, to heat the air passing over it without the use of an intermediate fluid such as steam or hot water. Warm-air furnaces and air-conditioning units are integrated into ducted distribution systems to control both temperature and humidity. 1l1ey are now engineered and built so that they are energy efficient.

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CHAPTER12: I !eating Systems

FU

TYP S

Oil 'TI1ere are various grades of fuel oil used by oil-fired furnac es and steam boiler s (FIGURE 12·1), with No. 1 and No. 2 being the most common. No. 5 and No. 6 fuel oils are known as "heavy" oils and must be heated if they are to flow. TI1ecombu stion and heating values for some common fuel oil grades are indi cated in TABLE 12-1. The heavi.er the grade of fuel used in an oil burner, the greater the care that must be taken to ensure that oil is supplied to the combu stion process at the prop er atom izing

Jacket

Waler heating coil

Flue baffles

Gas or oil burner

Combustion chamber

FIGURE12·1 Oil-fired steam boiler.

Combustion and Heating Values for Some Fuel Oil Grades Fuel Oil Grade

Heating Value (Btu/gal)

Comments

No. I No.2

132,900-1 37,000 137,000- 141,800

Small space heaters Residential heating

No.4 No.5 (Light) No.5 (Heavy)

143, 100- 148,100 l 46,800-150,000 149.400-152,000 151,300- 155,900

Industrial burners Preheating in general required Heating required BunkerC

No. 6

No. I and No. 2 fuel are both used (or residential heating purposes.No. 2 is slightl11 more expensive, but the fuel gives more heat per gallon used.No. I fuel oil is used in vaporizing pot-type burners. No. 2 is used in atomizing gun-type and rotary fuel oil burners.

151

SECTION 2: Building Systemsand Fire Protection Systems

temperature. If the temp era h1re is too low, the fuel oil will not atomize and evaporate, and the burn er will not operate efficiently. As a result, systems using No. 5 or No. 6 fuel oils have complex systems for heating the oil that usually require extensive pollution-abatement equ ipment to deal with the impuriti es in the oils. If such system s are present, the inspector should verify that this equipment is test ed periodically. Oil tanks, including their fill and vent pipes, should be checked for use of the proper materials and any signs of deterioration. Any leaks should be repaired, and spills should be cleaned immediately when necessary. Sawdust should not be used to absorb a spill because it adds to the risk of fire. Every oil supply line where it leaves the tank should have a safety valve that has a lead or other soft metal core that rnelts and closes the valve so that the system will not keep feeding oil to the heating equipment if the area is on fire.

Gas Liquefied Petroleum Gas, Liquefied petroleum gas, also called LPG, GPL, and LP gas, is a flammable mixture of hydrocarbon gases used as a fuel in heating appliances and vehicles . TI1ereare numerous variet ies of LP gas, including mL,es that are primarily propane, mixes that are primarily but ane, and, most commonly, mixes including both propane C 3 H 8 and butane C4 H 10 depending on the season-in the winter more pro pane and in the summer more but ane. Propylene and butylenes are usually also present in small concentrations. LP gas can be transported , stored, and used almost anywhere in the world. ft does not require a fixed network and will not deteriorate over time. LP gas is a clean-burning fuel. Originating mainly from natural gas production, it is also nontoxic and will not contaminate soil or aquifers in the event of a leak. Although it is nontoxic, it is an asphyxiant and is highly dangerous. It is a multipurpose energy so urce with more than a thousand applicat ions, from cooking, heating, air-conditioning, and transportation, to cigarette lighters and even the Olympic torch . Cautions are as follows: • TI1eflue gas temperatures of some units have become so cool that condensat ion of combustion gases within flues has become a major problem . Units with low temperature flue gases can generate highl}' corrosive gases that condense and can eat through masonry -lined or clay tile-lined flues causing a significant risk of fire and/or structural failure of the chimney. • LP gas is flammable like all petroleum fuels. It must be stored away from sources of ignition and in a well-ventilated area. • LP gas can be detected by a typically unpleasant odor of gas. • LP gas vapor is heavier than air. Any leakage will sink to the ground and accu mulate in low-lying areas. • TI1ereare special LP gas tanks that are specifically designed for use underground. • LP gas expands rapidly when the temperature rises, so whenev er a container is filled, sufficient space is left for expansion.

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CHAPTER 12: Heating Systems

• LP gas will cause natura l rubber and some plastics to deter iorate. Only use hoses and oth er equipme nt specificall}' designed for LP gas. Natural Gas. Natural gas is a combustible mixture of hydrocarbon gases. Although natural gas is formed primarily of methane, it can also include ethane, propane, butane, and pentane . TI1e composition of n atural gas can var}' widely, but TABLE 12·2outlines the typical makeup of natural gas before it is refined. In its purest form, such as the natural gas that is delivered to your home, it is almost pure methane . Metha ne is a mo lecule made up of one ca rbon atom and four hydrogen atoms and is referred to as CH 4 • TI1edist inctive "rotten egg" smell that is often associ ated with natural gas is ac tual!}' an odorant called mercaptan that is added to the gas before it is delivered to the end-user. iv1crcaptan aids in detecting any leaks.

Electricity Elec tr ic heating is an)' pro cess in which electr ical energy is converte d to heat. Common applications include heat ing of buildings, cooking, and industr ial processes. An electric heater is an app lian ce that converts elect rical energy into heat. T11eheating element inside every electr ic heater is simply an electrical resistor and works on the principle of Joule heating; an electric current through a resistor converts electrical energy into heal energ y. Alternative ly, a heat pump uses an electric motor to drive a refrigeration cycle,draw ing heat from a source such as the ground or outside air and directing it into the space to be warmed. Such systems can be desirable in that thq can deliver two or three units of heating energy for every unit of electricity purcha sed . As a "fuel" supply, inspectors need to check for excess heat of wires and breakers, because such may indicate over loading of the circuit, which can be a fire hazard, . -- - "' TABLE ·,12j -~;, • -J'

.,.,

••

• • -

Typical Composition of Natural Gas

• M,I

.. -

.,

Compound

Chemical Formula

Percentage

Methane

CH4

Ethane

C2H6

Propane

C3H8

Butane

C_, H,0

Carbon dioxide Oxygen

co, o}

Oto 0.2%

Nitrogen

N1

0 to 5%

Hydrogen sulfide

H2S

0to5%

Raregases

A,He, Ne.Xe

70%to 90%

0 to20 %

0to8 %

Trace

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SECTION 2: Building System s and Fire Prot ect io n System s

Solid Fuel Solid fuels are variou s materials used to provide direct heating usually through combustion (burning) in simp le heating systems. They are used in a very small percentage of buildings but need at least the same level of inspection attention. Solid fuels typically used to heat buildings include wood, charcoal, peat, coal, and pellets that can be made from wood, corn, wheat, rye, and other grains. Coa l was the fuel that powered the Industrial Revolution, from firing furnaces to running steam engines. Wood was extensively used to run steam locomotives. Both peat and coal are still used in generating electricity today. The use of some solid fuels (e.g., coa l) is restricted or prohibited in some urban areas because of the potential to produc e unsafe levels of toxic em issions. Other solid fuels, like wood, are being used m ore as heating techn ology improves. They tend to be m ore environmentally friendly and able to be rep lenished . In some areas, smokeless coal is often th e only solid fuel us ed. In Ireland, peat briquett es are used as smokeless fuel. They are also used to start a coal fire. The use of solid fuels requires carefu l safety in specti ons, becau se they are m ore difficult to ignit e, to regu late burn rate, and to ext inguish than th e liquid or gaseous fuels.

Geothermal Geothermal h eat ing relies on an energy exchange b etween th e air within the building being hea ted and the ground. Below 10 ft (3 m), the earth's temperature is fairly constant (genera lly betwe en 50°F and 56°F, or 10°C and 13°C) . Heat pump s extract heat from the gro und and use it to heat th e buildin g. Thermal efficiency is high, because no energy conversion is needed, but capacity fac tors tend to be low (around 20%), because the heat is mostl y need ed in th e winter . Th e only potentia l for fire is the electrical wiring at th e heat pumps.

Solar There are two m ajor con sider ations for fire safety of photovo ltaic (PV) system s: 1.

2.

Fires caused by PV compo nent s and systems, which are genera lly caused by ar cin g conn ect ions, which can be caused by a numb er of issues including, but not limit ed to, poor electrica l conn ections and buildin g/a rr ay movement. Fires caused by externa l sources but exacerbated by the PV array, as in the case of a roof fire under th e array, which can be very difficult for fire fighters to gain access to in order to extin guish .

This is a relatively new techn ological area, and many code and stan dard s developers are working with fire fighters and indu stry professionals to find approp riat e solutions based on a number of significant fires that h ave occurr ed. This code work will take a few years to mature and become standardized. At the moment, it is an area where inspectors simp ly need to be cogniz ant of con cerns and watch the evolving codes and stand ards closely.

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CHAPTER 12: Heating Syst em s

HEATING EQUIPMENT Furnaces (Warm-Air Systems) Filters, m otors, and dust build -up are items in which fires within th ese system s can occur . It is imp ort ant to ensure that du ct-m ount ed sm oke detectors app rove d for th e appli cation are in stall ed to shut down th e unit in th e event of on e of the se fires on all system s greater th an 2000 cubic feet p er minut e (cfm) . In th e larger of th ese "sm all" building s, system s with air handl ers gr eater than 15,000 cfm n eed to h ave sm oke da mper s on th e suppl y and return side, activated by duct-m ounted sm oke det ectors that shut down th e unit and close th e damp ers to contain sm oke from a fire in th e m otor, filter, or oth er thin gs in th e system . Imp roved equipm ent efficien cies and tight er buildin g envelope s have also created oth er n ew hazard s in buildin gs. A lack of adequa te combustion air can cause fossil fuel equipm ent to gen erate deadly carb on m onoxid e (CO) gas, whi ch can buil d up within a buildin g th rough in compl ete burning of fuel s. In additi on, th e lack of sufficient combu stion air can cause th e unit to reve rse th e natur al upw ard action of gravity vents and actu ally pull th e prod uc ts of combu stion back int o the bu ilding rath er than m ovin g th em out of th e buildin g. CO det ectors are being mandated for use in m ore of th e national codes or loca l reg ulations. They are still a goo d idea even if th ey are not requir ed by th e loca l code. A lack of proper cleara n ces betwee n unit s, du cts, and combu stible m ateri als can also be dan gero us.

Boilers Steam. The sight glass on a steam bo iler is an imp ort ant safety and op eratin g device,

as it allows th e h om eown er or inspector to see at a glan ce when th e steam boiler is low on water. Unlik e a hydronic heatin g boiler, som e of th e water in th e steam boiler is lost thro ugh th e bu ildin g's ra diator steam vent s at eac h heatin g cycle. Just h ow mu ch wa ter th e steam boiler will lose vari es wid ely depe ndin g on a numb er of facto rs. If a h eatin g boiler loses its water wi th out also being shut down , it will cert ainl y be dam aged by th e heat of the oil or gas bu rne r (or coa l or woo d), an d it co uld lead to a dan gero us explosion or fire. If th e stea m boiler has an autom atic wa ter feeder, you should still check th e water level (and clarit y) in the sight glass frequ entl y, but th e ri sk of a ru in ed bo iler fro m lost wa ter is of course mu ch less. A lack of proper clear ances be tween uni ts, du cts, and comb ustibl e m aterials can also be dan gero us. Hot Water. Press ure an d temp era tur e reli ef valves are installed on all m ode rn h eatin g boilers to release hot water an d press ur e should the b oiler's int erna l p ressur e or tem pera tur e rise to an unsafe level. A defective re lief valve is a latent safety hazar d, in that th e valve does n ot by itself cause a boiler to exp lode, but it m ay fail to protec t again st that event should oth er dangero us con diti ons causing over tempe ratur e or overpress ure arise in a heating boiler or wa ter heater. A lack of proper cleara n ces betwee n units, du cts, and combu stible m aterials can also b e dangero us.

155

SECTION 2: Building System s and Fire Prot ect io n System s

Solid Fuel Stoves Look for signs of structural failure, such as deformation, cracks, or holes. Most fires in metal factory-bui lt chimneys occur because of improper installation, use, or maintenance and include: • Improper chimney installation causing ignition of nearby wood framing . • Structural damage to the chimney caused by burning creosote (a black, tar-like substance that builds up inside the chimney and then burns). • Chimney corrosion resulting in wood framing being exposed to excessive temperatures. • Buckling and collapsing of the inner liner of the chimn ey. (This can result from too hot a fire, especially in high-efficiency stoves and in fireplace inserts, or from a creosote fire.) • Many serious fires also occur in masonry chimneys, usually from improper installati on or when the tile inner liner and the surrounding brick or block structure crack and separate . Such cracks may be caused by the igniti on of creosote. Smoke and heat can then escape and ign ite mat erial near the chimney.

Portable Units There seems to be an increasing trend for occ upant s to use portable devices to provi de indi vidu al or area heating to avoid turning up the thermostat. Thes e devices are not part of the building's systems, and building owners m ay not even be aware th at such units are being used by individual occ upant s. The co rds can be trippin g hazards , and fires are frequentl y reported from th ese units being too close to com bu stibl e materials or from wires and exte nsi on cords over he ating. Wh ere they are permitted, the wires and extension cords sh ou ld be in spec ted. Portable electrical hea ters with improp erly sized wir es and ex tension co rds can over h eat and cause fires. Unvented p or tabl e kero sen e hea ters have caused num ero us deaths and fires and should not be permitted in places of public assembly . NFPA 1OJ®, Life Safety Code®, and NFPA 5000, Building Construction and Safety Code, b oth prohibit such dev ices in education al occupancies, daycare faci liti es, hea lthcar e occ up anci es, detention and correctional occ up ancies, and in all residentia l occupa ncies excep t one - and two -fami ly dw ellin gs.

DISTRIBUTION SYSTEMS Warm-Air Systems A forced warm-air system uses ductwork to deliver heated air from a source (furnace, air handler, etc .) to eac h room. The furnace can produce th at h eat from any number of fuels: gas, oil, elec tricit y, wood, coa l, or a comb in ation of any fuels. Hybrid systems are becoming more popular. These syste ms use a boiler to produce hot water th at is delivered to a coil in the air hand ler of a warm-air system. 156

CHAPTER 12: Heating Syste m s

Air Duct Syst em Safety. Return air i11takes may draw in CO from the heating equipment if the proper amount of combustion air is not provided . Note that more indirect building defects and hazards, such as a toxic airborne mold reservoir or toxic gases or chemicals (such as sewer gas), may be picked up and distr ibuted through a building from one area to another by duct system defects.

Hydronic System s (Steam and Hot -Water Systems ) Hydronic heating systems use either hot water or steam as the medium for heat transfer. '.l11emedium is moved through a µiping loop b}' a circulator pump for hot water or natural pressure for steam to the various spaces to be heated. Some of the common items installed in the loop for the transfer of heat within spaces throughout the building are radiators, copper or cast iron baseboard, and radia nt loops. Hydro-air S)1Stems use a fuel-burning boiler or hot-water heater to produce hot water. Th e hot water is piped to a coil in an air handler, someti mes called a fan coil. Inside the air handler is a mu lti row coil, through which the hot water is circulated. Air is then passed over the coil and ducted to the space. An aquastat or time delay can be used to allow the coil to heat up before turning the blower on, preventing the discharge of cool air tha t can feel uncomfortable in heating mode.

Heat Pumps Because most component s of a heat pu mp system are identical to those of central airconditioning systems, readers shou ld review information on air-conditioning system fire and life safety inspection .

CLEARANCES A major consideration in the installation of any heat-producing appliance is its effect on nearby combustibles. \·Vood and other combustibles can ignite at temperatures well below their usual ignition temperatures if they are cont inually exposed to moderate heat over long periods of time, as the exposure removes whatever moisture is usnall}' present in the material. For this reason, installation clearances of equipment, ducts, piping, vents, and connec tors are of the utmost importa nce. Listings of tested heating equipment indicate the materials upon which the equipment can be mounted, such as combustible noors, fire-resistive floors extending specific distances be}'ondthe equipment, masonry floors,or metal-over-wood floors. For listed appliances, the manufacturer's instaUation instructions contain this information and should be with the equipment. Check the materials ,md consult the references for specilic products. Extensive information on clearances is given in NFPA 211, Stm1dardfor Chi11111eys, Fireplaces, Vents, n11dSolid F11 el-B11rni11g Applin11ces, and in NFPA 54, Nationnl Fuel Gas Code. Inspectors should always check these distances during inspections. In addition, the Fire Protectio11Handbook covers these mater ials thoroughl y by type of appliance; laboratory listings cover them by manufacturer's model. 157

SECTION2: Building Systemsand FireProtection Systems

COMBUSTION AIR As a result of energy conservat ion mea sures, buildings are being insulated more thoroughly , and cracks and crevices are being sealed. However, there must always be enough air available for combustion, for ventilation, and for replacing the volume lost in venting the combustion products to the outdoors. An 0>,11gen-starved fire in a boiler, furnace, stove, or water heater causes an incomplete combustion reaction, which can result in the vent becoming clogged with soot accumulations in addition to the pro duction of higher than usual quantities of toxic by-products such as CO. Additional air for ventilation also helps dissipate the heat that develops on the surface of the equipment and within the space that may enclose it. Eq uipment rooms tha t contain combustion equipment should be inspected to ensure that they have an adequate, positive means of supplying combustion air. This is especially important if the room contains any exhaust fans (including those in equipment such as clothes dryers), as they could draw a reverse flow of air down the stack or flue pulling CO back into the building. NFPA 54 contains specific reco mmendations on how properly to supply the air required for combustion and ventilation. A lack of adequate combustion air can be indicat ed by or can result in these heating system operating and safety concerns: • Gas burner sooting or odors with small amounts of soot or flame marks right at the gas bumer may indicate an operating problem but may not be producing CO. However, any soot produced at a gas-fired appliance, such as chunks of soo t found around a gas flue vent or draft hood, is a red flag that dangerous CO is potentially being produced and/or that a chimney may be blocked . Turn off the equ ipment and contact the heating service company or utility company immediately . • Improper oil burner system operation such as noises, rumbling, and so forth, should be fur the r investigated by a qualified contractor. • O il burner sooting or dirty operation produces the same concerns as with a gas burner as described above. • Burn marks on the boiler, furnace, or water heater are conditions that may be caused by a blocked exhaust flue and inadequate venting. Burn marks can also be caused by a collapsed or damaged combustion chamber liner, which is a serious fire hazard needing immediate attention.

SAFETYCO NTROLS Oil-Fired Equipment An electric power service shutoff switch is located near the oil burn er for the service technician, and an electric power emerge ncy shutoff switch, remote from the oil burner, is best located at the top of the basement stairs or in the nearby living space (you do not want to have to enter a smoke -filled basement to turn off the heating system in an emergency). The primary control, the most common type on modern heatin g boilers, controls the oil burner operation, turning the burner on or off as the boiler low-limit or high-limit temperatures are reached, respectively. A fusible link oil valve in the oil line is a safety

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CHAPTER 12: Heating Syst em s

valve that has a lead or other soft metal core that melts and closes the valve so that the system will not keep feeding oil to the heating equipment if the area is on fire. A cadmium cell or a stack relay is used to confirm that the furnace oil burner is operat ing properly and to avoid flooding the combustio n chamber with unburned oil. Modern heating boilers use a cadmium cell sensor, usually located inside the oil burner tube, to "see" the presence of flame and thus to ensure that the oil burner assemb ly stops pumping oil into the combustion chamber if flame ignition is unsuccessful. The cadmium cell is wired to a relay switch (usually a gray box with a red "reset" button located on top of the oil burner), which switches the oil burner off when a flame is not estab lished in the burner. If the red button on the cadm ium cell relay is sticking up and the oil burner has shut down, try "resett in g" the system by pressing the red reset button, but only once. If the oil burner does not turn on and run normally and continuously (no smoke, no loud noises, etc.) for at least 5 or 10 minutes after resetting the relay or pressing the reset button, do not keep resetting the system, because doing so can flood the combustion chamber with unburned heating oil, which is a dangerous condit ion . Have the system evaluated and corrected by a qualified contractor . Older oil burners may use a stack relay to accomplis h the same purpose of turning off the oil burner if the flame is not established. The "stack relay" is a bimetallic spring inserted into the flue vent connector located usually quite close to the heating boi ler between the boiler top and the chimney. The bimetallic spring warms in response to hot oil burner exhaust, confirming that combustion is taking place. If combustion is not occurr ing, a timer inside the stack relay turns off the oil burner to prevent flooding of the combustion chamber with unburned oil.

Pressure and Temperature

Relief Valve

A pressure and temperature relief valve is installed on all modern heating boilers to release hot water and pressure shou ld the boil er's internal pressur e or temperature rise to an unsafe level. The relief valve should be piped to a few inches from th e floor with the end of the discharge tube always in a visible loca tion, so that if it is leaking or open, the building owner or manager can observe that (unsafe) cond ition. Some very old h eat ing boilers may not have a relief valve install ed. Low-water cutoff sensors are installed on all steam and on some hot-water heating boilers. This is a sensor that turn s off the gas or oil burner should the water level or pr essur e in th e system fall below a safe level.

CHIMNEY AND VENT CONNECTORS Chimneys Chimneys have three primary function s or attributes no matter what type of fuelburning equipm ent is attached to them or what th ey are construct ed of: l. 2. 3.

They convey the products of combustion out of the building to keep th em from contaminating th e air inside th e building. They protect com bustibl e constru ction from catc hing fire. They maintain their structural stab ility while performing the above . 159

SECTION 2: Building System s and Fire Prot ect io n System s

Masonry Chimneys. A m asonry chimne y should be inspected along its entire length, so far as it is access ibl e. The inspector can exam in e the inside of th e chim n ey by placing a mirror in a connector opening or the clean-out opening and usin g capt ur ed sunli ght. A sufficientl y bright flashlight can also be used when su nlight is abse nt or offsets render it useless . On the roof, the inspector shou ld note the condit ion of th e mortar, the chimn ey lining, and the flashing and should look for evidence of cracking or settling . If a solid-fuel app liance is connected to th e chimney, th e in specto r should check to see that a spark-arrestor cap is installed and shou ld note the number of flues . In the attic and the bas ement, the inspect or shou ld check for cracks and loose m ortar . All chimney conn ect ions sho uld also be checked and m atc hed to th e approp riate flues and liners. If a solid -fuel appliance is connected to the chimney, no gas- or oil-fired equipment should be connected to it. If m ort ar ha s begun crumbling from between the bricks, open in gs can be expected to develop all the way through the chimney wall. The following is a list of common and important chimn ey defects that, individually or in combination, cons titute sufficient reason for requiring that a ma sonry chimney be repaired or rebu ilt:

• The design or prop ortionate dimensi ons of the chimney are structurally un so und . • There is evidence of settling or cracking because of in adequate footings or other caus es. • The chimney rests up on , or is wholly or par tly carried by, wooden floo rs, beam s, or brack ets, or it is hung by m eta l stirrups from wooden construction. The chimney is used to support any wooden floor or roof beams. • The chimney increases in size, ha s projecting masonry, or is set back within 6 in. (152 mm) above or below the rafters or roof joists. • The ch imney is unlined, and its wa lls are n ot as thi ck as required. • The mas onry is unb onded or improperly bonded, or the sections are not properly anchored or rein forced . • The mortar is weak. • Old mortar is decayed, because of the action of the flue gases, or it is weathering. The chimn ey is n ot properl y finish ed at top. • The brickw ork is not laid up aro und th e linin g. In ot her words, th e lining was dropped into place after the walls were constructe d. • Linin gs are cracked or broken. • There is no fire clay or metal thimble s at th e op eni ngs for conne ctors. • Connector openi ngs are found in more th an one story for a singl e flue, and n o prov ision h as been mad e effectively to close unu sed ope nin gs. • The flues show leakage in a smoke test. • Flue linin gs are not comp let e from 8 in . (20 cm) be low the con nector openi ngs to the top of th e chimn ey. • There is a reduction in th e cross-sect iona l area of a flue at any point. • The flue is positioned at a grea ter th an 308 -degree ang le to ver tical. • The chimn ey does not extend at least 3 ft (90 cm) above a flat roof or 2 ft (60 cm) above the edge of a gab le or hipp ed roof.

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CHAPTER 12: Heating Systems

• Woo dwork, parti cularly beam s and j oists, is within 2 in. (5 cm ) of the outsid e surfac e of th e entir e chimn ey. Factory-Built Chimneys. Factory -built chimn eys are lightweight assembli es and goo d draft pro duc ers (FIGURE12-2). Som e type s resembl e Type B gas vent s but are larger and h eavier. The mat eri als used in their con structi on me et cert ain requir em ent s for h eat and corro sion resistanc e. Factory-built chimn eys are available as listed assembli es for low- and m edium-h eat applianc e servic e. Th ey sh ould be insp ected in accord ance with the manu factur er's installation instructi ons , whi ch should be located with th e equipm ent. Metal Chimneys, Metal chimn eys are suitabl e for all classes of appliance s, but they are not subj ected to safety testin g of any kind . The m ajor hazard to loo k for wh en inspect ing these chimn eys is in adequ ate clearan ce from combu stibl es where th ey pen etrat e floo rs, ceilin gs, and ro ofs. The cond itions und er wh ich m etal chimneys can b e used are quit e limit ed and are spelled out in detail in NFPA 211, Stan dard for Chi m neys, Fireplaces, Vent s, and Solid Fuel-Burn ing Ap p liances.

Q::_:::::::~-

-

-

::::::::: DC~ =:::;;;---

Diskap Exten sion stub

Housing assembl y

FIGURE 12-2Typical factory- b uilt (Type L) ch im ney.

Vent Connectors Flue Vent Connectors for B or L Vents. A vent conn ector conn ects gas equi pm ent to a flue or chimn ey. Appli ances havin g draft hoo ds an d insta lled in an attic or con cealed space mu st use Type B or L conn ectors. Appli an ces installed in base m ents can use Type B or Typ e L or m etal pip e (0.0304 in . [0.0772 cm] thi ck) or aluminum pip e (0.0 12 in. [0.0305 cm ] thick). Gas -fired equip men t should no t be connected to any flue serving so lid fu el ap pliances. Multiple Gas Vents into a Single Flue. Wh ere two or mor e vent conn ectors ent er a comm on gas vent , chimn ey flue, or sin gle wall m etal pipe, th e sm aller conn ector shall enter at the high est level consistent with available h eadroo m and cleara nce to comb ustibles. Avoid un necessary b end s and secur e all joint s with shee t m etal screws or other approved m eans.

161

SECTION2: Building Systemsand Fire Protection Systems

VISIBLEBUILDING CONDITIONS RISKING CO HAZARDS The fact that you cannot see or smell dangerous CO gas does not mean that there is nothing to look for when assessing the safety of heating equipment. Not only are there easil}' spo tted install ation errors, but also ther e may be more subtle but easil)' visible error s if you know what to look for. This is by no means the complete list of errors that can cause dangerous CO exposure in buildin gs, but here are some common errors that create conditions that can cause dangerous levels of indoor CO:

• Space heaters;T11e improper use of gas- or kerosene-fired heaters can produce high indoor CO levels. Never go to sleep in an enclosed space with a space heater left operating. In addition to the CO hazard s, there is a risk of oxygen depletion, which can also lead to asphyxia tion. • Gas-fired centralheating equipment combined with: • Improper venti11gincluding blocked, und ersized, oversized, or missing parts or improperly sloped chimney or flue. A variety of errors can cause a failure to vent combustion gases out of the building, allowing dangerous flue gases to build up indoors. • Inadequate co111b11stio11 air. Jf a heating appliance is installed in a small confined space, it must be provided with outside combustion air. A service technician ma}' tune and inspect a gas-fired boiler with the boiler room door open, finding that it seems to operate fine. When he or she closes the door upon leaving , there may be an inadequat e or no openLng for combust ion air to get into the room and the equipment. • Velltingsmall appliances into largecold chimlleys.Installation of small, higher efficiency gas-fired equipment in older homes where the appliance is vented into a large masonr}' chimney . In such instances , the heater ma)' never develop sufficient heat to create an updraft actually to vent the exhaust gases up the chimney. Sometimes, water heaters are Jeft venting into a too -large, too -cold masonry chimne}' after a gas-fired boiler is converted to a high -efficiency direct-vent (no chimney) unit. • Car exhaust seeping into rooms adjoining or even above a garage where car engines are left running. • Gas-fired water heaters are often found improperly venting directly into a basement utility room or even directly into a living area or bedroom.

BlBLIOGRAPHY ANSI/UL 103, Chim11eys, Factory-BuiltReside11tinl 7)1pe and BuildingHeatingAppliance, Underwriters Laboratories, Inc., Northbrook, TL. ANSI/UL 959, Medi11lllHent Appliance Factory Built Chimneys, Underwriters Laboratories, Inc., Northbrook, IL. Boilern11dPressureVesselCode,Section I\~ American Society of Mechanical Engineers, New York, NY.

162

CHAPTER 12: I !eating Systems

Cote, A. E., ed., FireProtectionHmrdbook,20th ed., NFPA, Quincy, MA, 2008. Gns and Oil Eq11ip111ent Direct01y, Underwriters Laboratories, loc ., Northbrook, (issued annuall y).

IL

NFPA Codes, Standards, and Recommended Practices

See the lalesl version of the NFPA Cata log for availability of curr ent editions of !he following documents. NFPA 30, Flammn/Jleand Co111/J 11sti/Jl e Uq11idsCode NFPA 31, Standardfor the lnstal/atio11of Oil-B1m1i11g Eq11ip111e11t NFPA 54, National Fuel Gas Code NFPA 58, Liq11efiedPctrole11111 Ga Code NFPA 70®, National Electrical Code® NFPA 85, Boiler a11dCom/Justion Systems Hazards Code NFPA 86C, Stmrdardfor Ind11 strial FurnacesUsinga Special ProcessingAtmosphere NFPA 86D, Stmufardfor Industrial Frmwces Usi11x\lt1cu11m as mi Atmosphere NF PA 90Il, Sta11dardfor the l11stallati on cf Warm Air Heating and Air-Co11ditio11i11g

Systems NFPA 97, Stmidard Glossmy of Terms Relati11g to Chi11111eys, \lents,and He11t -Prod11ci11g

Applimices NFPA 101®, Lije Safety Code® NFPA 2 1 l, Standardfor Chimneys, Fireplaces , Vents,and Solid F11 el-B11rni11g Appliances NFPA 5000, Building Co11Strnctio111111d Safety Code

163

CHAPTER

13 AlR-CON DITION ING AND VENTILATING SYSTEMS Allan B. Fraser

This text is specificall}'focused on fire and life safety inspections; it is not an exJiaustive inspection checklist for all parts of air-conditioning and ventilating S}'Slems.It is not concerned with the efficienc}',effectiveness,or desirabilit}'of any system, but rather only with those items or conditions that have the potential for causing or increasing the danger of fires or other life-threatening condi tions. Why is this type of inspection important? Isn't it redunda nt? Haven't building or mechanical inspectors already checked to ensure that the installer installed the system properly? The answer is yes, they probably have, but fire and life safety are important enough to warrant a second inspection of some items. Call it a good foil-safeprocedure. In addition, as any system of moving parts ages, things malfunction or break over time, making regular inspections important. The vast majority of air-conditioning systems and their components do not have a lot of potential to create a fire, but there is some potential for a fire in the motor, belts, or .filtersthat, in the forced-air systems, can magnify the life-threatening effects of even a small fire by spreading smoke and lethal gases throughout occupied spaces of an entire building very quickly. If the safety devices are not in place and working properly, escape can be very difficult, if not impossible. This chapter is intended to provide fire and life safety inspectors sufficient information about what items and devices need lo be inspected and to provide snfficient information for them to be able to assess when a qualified contractor or engineer shou ld be consulted to assess further and/or repair the part(s) in question.

GENERAL Air-conditioning systems control the temperature and humidity of air, dean it, and distribute it to meet the requirements of a conditioned space(s). 1l1ere are many types of air-conditioning systems that may be used to provide filtered, cooled, and dehumidified air in summer and heated, hnmidified air in winter. Some of the mechanical equipment associated with air-conditioning systems can cause damage to the building's components or the system itself and cause injury

CHAPTER 13 : Air-Conditioning and Ventilating Systems

Expansion Valve

Zone

Exhaust Air Fan

FIGURE 13·1Three major compone nts of air-co ndi tioning-re lated duc ted, forced-air systems.

to individ uals if imprope r!)' started, stopped, or o r erated . 'D1e status of a piece of equipm en t or a system shou ld never he changed if its operation is not completely und erstood. Whe n inspec ting air -conditioni ng and ventilati ng systems, inspectors must und erstan d what the S)'Stem consists of and how it is supposed to function . TI1is charter wi ll discuss only air-con ditio ning related to ducted, forced-air systems. TI1ese systems have three major component s: the ai1·-inta ke system, the conditioni ng equip • 13-1). me nt, and the distribution {supply) system (FIGURE

COMPONENTS Air- Intake System Some system s mLx fresh air with recirc ulated air, wh ereas others may use fresh air exclusive ly. In either case, there mu st be an air -intak e duct to introdu ce fresh air into the system . The open ing of this du ct sho uld be protected with a gr ill or screen, with the prop er net -free vent area to r revent foreign material s from entering the system while still allowing the system to pull in the required cubi c feet per minute of air (FIGURE13·2). The most com mon scree nin g is wire mesh with an opening dimension no smaller than¼ in. (6.4 mm) and no larger than ½ in . ( 12.7 111111),because smaller d imensions tend to become clogged too eas ily and larger dimensions fail to exclude many commo n vermin . TI1e inspec tor sho uld make sure tha t the d uct is no t broken, clogged, or m issing and that it is free of rubbi sh, mold, and debris . 165

SECTION 2: Building Systems and FireProtection Systems

FIGURE 13-2Ducts protected with a grill or screen prevent foreign materials from enteri ng the system w hile still allow ing the system to pull in the requ ired cu bic feet per n,i nute of air.

Rated Enclosures Unless the equipment consists of simple rooftop or ground-mounted package units, fims, air -heating and -cooling units, and filters should be installed in a room that is separated from the rest of the building by construction with a 1-hour fire-resistance rating. Doors to these enclosures are to be I-hour labeled assemblies with automatic closers . Most building codes usually require large units above a certain energy input capacity to be in separated rooms. Also, units incorporating combustible filtration beds, such as activated carbon, can pose a serious fire hazard. Automatic sprinklers not otherwise required to be present in the building may, with the approval of the authority having jurisdiction, be substituted for such fire-resistive enclosures but are of little effectiveness if installed only within the room. TI1e fuel and the ignition source are within the equipment, which is designed to exclude water and any particulates present in the room .

Automatic Shutdown Some systems use smoke detectors to stop the fan and close dampers during a fire. In accordance with NFPA 72:.ID , National Fire Alan11and Signaling Code, it is important to use this type of detector to provide effective detection and avoid nuisance alarms. These detectors cannot function properly if there is too little or too much airflow over them. ll1ese devices should be inspected and tested periodically. 166

CHAPTER 13: Air-Conditioning and Ventilating Systems

Housekeeping The inspector should also inspect equ ipm ent rooms to make sure the}' are clean and that nothing is being stored in them. Such enclos ures are often improperly used to store air filters, paper products, and light bulbs; they should not be used to store anything.

Cooling Equipment 111ehazards of cooli11g equipment are related to the hazards of electrical installations and to those of the refrigerant itself. All common refrigerants are toxic to some degr ee, so a leak in the system can be hazardous to health and life safety. In some instances, exposure to high conc entrations of halogenated refrig erants can manife st itself in the victim as card iac arrhythmia and be mistakenly assumed to be a heart attack. Some refr igerant s present a combustibi lity hazard as well, and all common systems incorporate combustible liquids as internal lubricants continuously circulated through o ut th e entir e system . An often unr ecogniz ed probl em assoc iated with refrigeration units .is the sudden rupture hazard of the pressuri zed refrigerant. 111efire experience of air-conditioning refrigeration units is generally good as long as the cooling equipment is properly installed and maintained. The inspector should be sure to check the frequency and quality of maintenance performed on the equipment and the housekeeping in the vicinity of the equipment. Aga in, these rooms frequent I>' end up being used to store everything from oflice supplies to chemicals to lawnmowers. Refrigeration machinery rooms are not Lobe used as storerooms. Recommendations for the in stallation of mechanical refrigeratio n equipment are contained in American Society of Heat ing, Refrigerating and Air-Co nditioning Engineers/ American National Refrigemtio11(see Standards Institute (ASH RAE/ ANSI) 15, Safety Codefor Meclia11ical the Bibliography).

Fans Lack oflubrication and accu mulation of dust are two of the greatest enemies of fans and motors. fioth can cause the equipment to overheat so much that it actually becomes an ignition source. TI1e inspec tor should check the fan belts for wear and proper tensioni ng and should ensure that the proper number, size, and con.figuration of belts is present. They should be adjusted or replaced as necessa1y Although fans are often located in places that are difficult to reach, they should nonetheles s be included in the inspection program.

Air-Cleaning Equipment and Filters The purpose of most filters and air cleaners is to remove entrained dust and other particulate matter from the air stream . TI1e filtered particles accumulate in the filter or on the air cleaner collector plates and, if ignited, could burn and produce a large volume of smoke. The products of combustion could be circulated throughout the building by the air distribution system , posing a threat to life and potential for sign ificant property damage. 167

SECTION 2: Building Systems and FireProtection Systems

Many systems have pressure difference gauges that visibly or audibly indicate an excess ive pressure drop across the filters, letting the occupants !mow that the filters should be cleaned or replaced. Filters should have either a Class l or Class 2 rating of Air Filin accordance with Underwriters Laboratories (UL) 900, Test Pe1for111mrce ter Units. J\fost systems have disposable filters, which should be discarded when dirty and replaced with new clean filters. Some systems have a washable medium, which should be cleaned in accordance with the manufacturer's instructions and recoated with adhesive . 111isadhesive must have a flash point not lower than 3258°F (1638°C) as measured in the Pensky-Ivlartens closed tester [American Society for Testing and Niateria ls (ASTM) D-93, Stmuiard Tes/for FlashPoint by Pensky-MartensClosedTester]. Electronic air cleaners use electrostatic precipitation to remove particu late matt er. Entrained particles pass through electrostatic fields and are collected either on a filter or on charged plates. Because electronic air cleaners use potentially lethal voltage and current combinations, they are equipped with interlocks that shut down the unit if a door or access pa nel is opened . 111e in.~pector should check that the interlocks ,1re intact and have not been bypassed . Some systems have an automatic wash cycle for proper plate operation. These systems should be examined to ensure they are operating properly and to ascertain that the correct cleaning solvents are being used. Other systems use disposable filters, which are simply discarded when dirty and replaced with new, clean ones. Gas absorption systems are common!) ' used to remove volatile organic compounds that can have unhealthful effects or cause offensive odors. TI1ese filtration units use materials that can be fire, health, or reactive hazards. The units should be carefully examined for compliance with the manufacturer's installation and maintenance instructions. TI1eir contents should be properly and clearly identified, with the appropriate placarding per NFPA 704, Standard Systemfor the Identification of the Hazards of Materialsfor EmergencyResponse,in place . Conditioned air is distributed throughout the building b)' means of the duct S)'Stem. During a fire, this same duct system could disperse smoke and toxic gases instead of breathable air throughout the building.

Ducts Generally, ducts are of metal, masonry, fiberglass, or other approved materials. ASHRAE and the Sheet Metal and Air-Conditioning Contractors National Association publish information about the construction of ducts. NFPA 90A, Sta11dardforthe Installation of Air-Conditioning and \lentilati11gS)•stems, and NFPA 90B, Standardfor the bistallation of Warm Air Heating and Air-Conditioning Systems, contain informa tion about construction and installation practices. UL 181, Facto1y-J\tlnde Air Ducts and Connectors,classifies duct materials accord ing to flame spread, smoke developed, and flame penetration. Class O materials have a flame spread and smoke developed rating of 0. Class l materials have a flame spread rating of25 or less, with no evidence of continued progressive combustion, and a smoke developed rating of not more than 50. Class 2 materials have a flame spread rating greater than 25 but not more than 50, with no evidence of continued progressive 168

CHAPTER 13: Air-Cond ition ing and Ventilat ing System s

combust ion, and a smoke develop ed rating of n ot m ore than 50 for the in side surface of the duct and not m ore than 100 for the outside surface . Class O and Class 1 mat erials must pass a 30-minute flam e pen etrati on test, and Class 2 mat erials mu st pass a 15-minut e flame penetr ation test. UL 181 also characterizes duct material resistance to fungal growth, becau se duct s can also harb or health hazar ds in the form of debris and biologicals. All duct systems shou ld be regularly inspected and, if nec essary, cleaned to mitigate the health and fire hazards . Ducts can create b oth ver tic al and h orizontal opening s in fire barriers. Where the ducts pass through fire barrier s or fire walls, adequate firest oppin g must be provi ded to seal th e space between th e duct walls and the edges of th e opening. If prop erly install ed and firesto pped, steel sheet metal ducts in the thickne sses comm only used can protect an open ing in a fire barrier wa ll for up to 1 hour.

Dampers Openings in a fire wall, ceiling , or floor ma y have to be prot ected with a fire damp er or combin ation fire/sm oke damp er. These damp ers are m ounted in h eavy-ga ug e metal sleeves, which require cleara nc es aro und them to permit free expansion of th e damp er and its sleeve in or der not to bind th e mechani sm and int erfere with its prop er op erati on . The perim eter is fitted with m etal angle s, which keep th e damp er in place during th e fire and help to seal off the required gap around them. Dampe rs sho uld be inspec ted, cleaned, and tested for prop er opera tion at leas t once every 4 years . Fire damper s are listed in accordance with UL 555, Fire Dampers. Penetrations of ceilings that are part of fire -resistive floor/ce iling or roof/ceiling assembli es requir e ceilin g damp ers. Ceilin g dampe rs are differe nt from fire damp ers in that th ey also retard th e passage of he at and not just flam e. Ceiling dampers are listed in acco rdan ce with UL 555C, Ceiling Damp ers. Fir e damper s are effective in lim itin g th e passage of flam e, and ceilin g damp ers are effective in limiting the pa ssage of b oth flame and heat, but n eith er is very effective at limiting th e passage of sm oke. Sm oke damp ers or combination fire/sm oke dam pe rs are necessary to protect smoke barr ier penetrati ons. These dampers mu st b e arra nged to close on the dete ction of smok e. NFPA 72® provide s guid ance for th e proper app lication of smok e detectors for both early detecti on and proper contro l of these dampers. This app roac h will limit sm oke migration within buildin gs thro ugh th e du ct system s. Smo ke dam pers are listed in acco rd anc e wit h UL 555S, L eakage Rat ed Damp ers for Use in Smoke Contro l Systems. Co mbin ation dampers are listed und er both of th e app licable categories . Fire and ceiling damp ers can fail to close prop erly if the airfl ow throu gh them is not stopped prior to th eir operat ion. In suc h systems, th ese damp ers should be specifically listed for dynamic ope ration. Smoke and combin ation fire/s m oke damp ers will always be dynamic operatio n damp ers, because they are opened an d closed wit h electri c m otors actuate d by smoke detection. Dampers listed for dyn ami c operat ion will state on their labe ls th e m aximum velocity of air th ro ugh th em. If m ore th an on e damper is ganged together to pro tect an openin g, th e velocity of air must be calcul ated 169

SECTION 2: Building System s and Fire Prot ect io n System s

on the assumption that on ly the sma llest area damper is receiving th e entire airflow of the duct. CAUTION: The inspector must exercise extreme cauti on when testing any damper for operation, because doing so can be very dang ero us. A sudd en powerful movement of the mechanism can sever fingers or hands.

Smoke-Control

Systems

Two recognized approaches to controlling smoke in buildings make use of the airconditioning system. The passive approach requires that smoke dampers be closed in coordination with do ors and other such assemblies protecting the smoke barriers that define th e smok e zone involved. In the active approach, the air-co nditioning system is sometimes used to exhaust the products of combusti on to the outdoors to prevent smoke migration from th e fire area. Smoke-control systems are necess arily complex to test and inspect, because they must involve architectural elements such as floors , wall s, doors, and wind ows. They also involv e the electrical power system, the fire alarm system, the building manag ement and control system, the fire spri nkl er system, and the building heating, ventilation, and air-conditioning systems.

Ventilating Systems Special ventilation system s are often needed to rem ove flammable vapo rs, corro sive vapors or fum es, grease- laden air from cooking equipment, or combustible dusts from an oc cup ancy . Am ong the hazards such systems present is the possibility th at sparks generated by fans, foreign material s in the airstream, or overheat ed bearing s will ignite th e flamm able material s or vapors. To reduce the hazard of fire, fans should be of noncombustibl e construction, accessible for m aint en ance , and structurally sound enough to resist wear. Occupants also should b e able to shut the fans down from a remote location. In systems used to exhaust flammable so lids or vapors, fan blades and housing s should be constructed of nonspa rking material to minimize the possibility of spa rk gen era tion. Electric al wiring and m oto rs are covered in NFPA 70®, Na tional Electrical Code ®. In systems used to exhaust corrosive vapors, it is often nec essary to use nonmetallic materials suc h as fiber-rein forced plast ic, comm on ly but imprecisely refer red to as "fiberglass:' CAUTION: The insp ector mu st exerc ise caution because some labo ratory exhaust systems can con tain depo sits of extremely ha zar dous materials such as crys tallized perchloric acid , which can produce violent explosions when sudden ly or sharpl y disturbed. Lab oratory exhaust systems servin g fum e h oods and the like are n ot permit ted by NFPA 45, Standard on Fire Protection for Laboratories Using Chemica ls, to have automa tic fire dampers incorporated into th e du ctwork. Com m onsen se extr apo lation would imply that smoke dampers should also be exclud ed . These specia l exhaust systems should b e ind epe nd ent of oth er ventil atin g systems and of on e anot h er. They sh ould be vented dir ectly o utd oors or, in som e very sp ecial cases, to approved containment or incineration systems by the short est ro ute an d should not pass through fire wa lls. For specific hazar ds, these systems might cont ain 170

CHAPTER 13: Air-Conditi o ning and Ventilat ing System s

special extinguish ing systems. A schedule for inspecting, testing, and cleaning the system should be developed if one is not already in use.

MAINTENANCE A maintenance and cleaning schedule is the key to safely operating air-conditioning and vent ilating systems. When inspecting the equipment, the inspector should look for signs of rust and corrosion, especially on moving parts; check the condition of the filters and the electrical wiring; examine air ducts for accumulations of combustible dust and lint; and recommend cleaning if necessary. The fire protection devices assoc iated with the system, including but not limited to fire suppression and smoke-control equipment, alarms, and fire and smoke dampers, should be tested periodically as part of the maintenance program. If inspectors do not witness these tests or conduct them themse lves, they shou ld ask to see the records of the tests that were performed. Such records should be specific as to the particular devices, both individually and the systems as an integrated whole, that were tested. They should specify by whom and on what dates th ese tests were conducted. The records should contain the deficiencies discovered and the remedies implemented to remove and, if possible, avoid such deficiencies.

BIBLIOGRAPHY ASHRAE/ANSI 15, Safety Code for Mechanical Refrigeration, American National Standards Institute, New York, NY. ASTM D-93, Standard Test for Flash Point by Pensky -Martens Closed Tester, American Society for Testing and Materials, Conshohocken, PA. Cote, A. E., ed., Fire Protection Handbook, 20th ed., NFPA, Quin cy, MA, 2008. Cote, A. E., and Linville, J.L., eds ., Industrial Fire Ha z ards Handbook, 2nd ed ., NFPA, Quincy, MA, 1984. UL 181, Factory-Made Air Ducts and Connector s, Underwriters Laboratories, Inc., Northbrook, IL. UL 555, Fire Dampers and Ceiling Dampers, 3rd ed., Underwriters Laboratories, Inc., Northbro ok, IL. UL 555C, Ceiling Damp ers, Underwriters Laboratori es, Inc. , Northbrook, IL. UL 555S, Leakage Rat ed Dampers for Use in Smoke Con trol Systems, Underwrit ers Laborato rie s, Inc ., Northbrook, IL. UL 900, Test Performance of Air Filter Units, Underwriters Labor atori es, Inc. , North bro ok, IL. NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Catalog for availability of curr ent editi ons of the following documents . NFPA 45, Standard on Fire Protection for Laboratories Using Chemicals NFPA 70®, Natio nal Electrica l Code® 171

SECTION 2: Building Systems and Fire Protection Systems

NFPA 72®, Nntionnl FireAlnrlll n11dSignalingCode NFPA 90A, Stn11dnrd for the !11stnllntio11 of Air-Conditioning n11d\fc11tilati11g Syste111s NFPA 90B, Standard for the I11stallatio11 of War111 Air Heating and Air-Co11ditio11i11g Sysfellls NFPA 91, Sta11dnrdforExhaust Systemsfor Air Conveying of \fnpors,Gnscs,Mists, {1//d No11co111b11stible ParlirnlaleSolids NFPA 92, Standardfor Smoke Co11trol S/m1d11rds NFPA 96, Sta11dardfor \fe11tilatio11 Control and Fire Protectio11of Co111111ercinl Cooking Operations NFPA 101®, L!fe Safely Code® NFPA 704, Standard Syste111 for the lde11t!ficatio11 of the Hazards of Materialsfor Elllergency Response

172

CHAPTER

14 SMOKE-CONTROL SYSTEMS NJ.ichael]. Ferreira,PE, NISFPE

Smoke -control systems are provided in many buildings as an added measure of protection over and beyond that provided by traditional fire protection systems, such as auto matic sprinkler and fire alarm systems. Smoke -control systems are most often required for buildings where occupant egress can take an increased amount of time or involves greater hazard, such as for high-rise or underground buildings. Smoke control is also required for large-volume spaces such as atria, malls, or theaters, where high ceilings may impede the ability of the installed sprinkler systems to activate and control or extinguish a fire. Smukc:-wnlrol systems are therefore provided as a means to control the large quantity of smoke that can be produced from these fires. Smoke-control systems are often complex in design and involve various compo nents that include building mechanical and heating, ventilation, and afr-conditioning (HVAC) equipment, electrical equipment, fire alarm systems, and architectural features. Historically, two problems have plagued smoke -control systems and affected their long -term viability as building protection systems. The first is the failure to maintain proper design and testing documentation for the smoke -control system over time. The second is the failure properly to test the system to ensure that it is operable and will function properly in the event of a fire. Maintenance of proper design and testing documentation is critical to the long-term functionality of a smoke -control system. Should fire inspectors seek to test a S)'Stem, it is important that they first understand how the system was intended to operate. This requires documentation pertaining to the original design, including design reports, drawings, and sequences of operations . Periodic testing documentation allows the inspectors to assess how the system has been performing over time and whether there has been any degradation of performance. Often, the failure to maintain this documentation hinders the ability of the fire inspector to understand the intended system operation and to perform all of the tests that may be needed. Inspection and testing must be performed both at the time a smoke -control system is first i11stal1edin a building (commissioning testing) and then at predetermined intervals over the life of the building (periodic testing). Testing may be performed

SECTION2: Building Systems and Fire Protection Sy'items

by fire inspectors or an approved third party that performs the testing and provides documentation of the testing for the fire inspectors to review. Too often, periodic testing is neglected and systems are tested infrequently, if at all, after the building is commissioned .

DESIGN OBJECTIVES Over time, smoke-contro l design objectives have evolved from the use of approaches that involved simple prescriptive features or ones based on prespecified air change rates to the use of approaches based on more scientific calculations that anticipate and respond to the expected behavior of the smoke . For example, early codes specified that break-out windows be provided at the perimeter of a high-rise building on each floor to allow the fire department manually to open the windows to vent smoke. Active me chanical systems were often designed to provide a specified air change rate, most often six air changes per hour , to vent smoke , irrespect ive of the particular geometry of the space or the fuel load contained within. More recent codes and standards have progressed to the point where airflow rates to pressurize a space or exhaust smoke within a space are determined as a function of design fire size or the properties of the smoke being produced. Even in the more recent codes and standards, there has been some confusion as to what objectives a smoke -control system was designed to meet. Terms such as "smoke control" and "smoke management" were interchangeably used along with more objective-based language such as pressurization/exhaust/airflow systems. National Fire Protection Association (NFPA) standards used the term Slilokecontrol to refer to pres surization systems, as defined in NFPA 92A, Reco111111e11ded Pmclicefor Smoke-Co11lrol Systems, and the term smoke 111nnnge111e11t to refer to those systems designed to protect large-volume spaces including atria, as defined in NFPA 92B, Smoke lvln11nge1ne11t Systeins i11Malls, Atrin, and Lnrge Areas. The NFPA Committee on Smoke -i\ilanagemen t Systems has recently clarified the terminology pertaining to the various types of smoke-control systems in the new standard NFPA 92, which combines the previously separate NFPA 92A and NFPA 92B. NFPA 92 uses the overarching term smoke control to define any active or passive system used to mitigate the impact or spread of smoke. Two different subclassifications of smoke-control systems were also delineated and are referred to as s111oke-co11tai11111ent and snwke-111mwgement systems.

Smoke-Containment

Systems

A smoke-containment system is defined as an active or passive system designed to contain smoke to a single smoke-control zone, the zone of fire origin in the build ing. Active systems use mechanical airflow to create pressure differentials across zone boundaries to contain smoke. Passive systems use smoke-tight barriers to contain the smoke, generally with no pressure differential impo sed across the barrier. Examples of smoke -containment systems includ e zoned smoke -control systems in high -rise buildings, which may include a combination of stair pressurization systems, elevator pressurization S}'Stems, corridor supply/exhaust, or floor supply/exhaust to 174

CHAPTER14: Smoke-Control Systems

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contain smoke, usually to a single floor. Passive smoke -containment systems are often found in hospital buildings, where two separate smoke compartments are provided on each floor, separated by a smoke barrier, to allow for horizontal relocation of patients in the event of a fire. Two ways to design pressurization systems to provide containment to a single floor of a building are shown in FIGURE 14-1and FIGURE 14-2.A positive pressurization system, where air is supplied to all spaces adjacent to the zone of fire origin, is depicted in Figure 14- 1. A negative pressurization system, where smoke is exhausted from the zone of fire origin to create a negative pressure with respect to adjacent zones, is depicted in Figure 14· 2. Although both approaches will contain smoke when the system airflows are properly balanced, the negative pressurization system has the benefit of removi ng smoke from the building.

Smoke-Management Systems A smoke-management system is defined as an active or passive system designed to manage the exposure of occupants within the zone of fire origin to the smoke from a fire. Smoke -management systems are found in malls, atria, and other large -volume spaces . Active smoke-management systems use mechanical ventilation to exhaust

175

SECTION 2: Building Systemsand Fire Protection Systems

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Building Systems and Fire Protection Systems

FIGURE 14·8Measuring door opening force for stair door under pressureusing spring-loaded door force gauge.

impact of sta ck effect. When performing commissioning testing for a compen sating stair pressuri zatio 11system , it is important to test all potentia l failure modes. In general, it is more acceptable to have a lower pressure difference in the stair than to overpres surize the sta ir, causing excessive door opening forces that imp ede occupant access to the stairs . Where elevator shaft pressurization is used, it is typical to use this method with elevators recalled to the floor of elevator recall to mi11imize the impact of piston effect on the pressuri zation systems . Pressures across the elevator doors shou ld be made after elevator reca ll. Tt is important to verify the prop er operation of the elevator doors un der the maximum design pressure for the system, including the impact of stack effect. Manufacturer data on the operation of elevator doors unde r pressure are not readily available; thus it is important to ensure that door s will operate properly under pres sure to allow occupant s to exit the elevator cabs. Demonstrat i.on testi11gis sometimes performed to provide a visual confirmation that the smoke-management system functions as designed. Visible smoke from a smoke generato r or smoke "bomb" has been commo11ly used as a means for testing the perfor mance of smoke -control systems . "Cold" smok e testing and "hot " smoke testing have been used in the past to test many smoke -control systems. Cold smoke testing in high-ceiling spaces has several 186

CHAPTER14: Srnoke-Conlrol Syslems

limitations. Because the cold smoke has limited buoyancy, visibility conditions at vari ous points within the atrium may vary substantially from those expected in real fires. 'The quantity of cold smoke produced would not adequately represent real fire conditions, neither in the amount of buoyanC)' produced nor the optical properties of the smoke. At best, cold smoke testing in high-ceiling spaces serves as an indication of the direction of smoke movement because of mechanical smoke exhaust from the space. Smoke layer position cannot be adequately determined via cold smoke testing . A testing method known as a "hot smok e test" has been used to show local authorities that atrium smoke -management systems cause smoke to be evacuated as intended. An example of a hot smoke test is an apparatus used for standard atrium smoke management systems where air is heated by a gas burner to produce a buoyant plume. Cold smoke in the form of smoke bombs is introduced near the base of the plume, so it may become entrained by the buoyant air to more close!)' simulate smoke movement generated by an actual fire. The general intent of demonstration testin g is to provide a visual confirmation that a smoke-management system is functioning as designed . However, caution must be taken that the testing method is an accurate simulation of the conditions that would be produced by a fire condition. If demonstration testing is used, a detailed test methodol ogy should be developed that describes the information to be obtained from the test, the assumptions implied, and the applicabilit) ' of the final results.

Documentation At the completion of testing, a comprehensiv e commissioning test report should be prepared that documents the results of the testing. 1he methodology used for test ing during commissioning must be clearly dornmented, explaining what constitutes as pass or fail condition. The report should include a summary of the results obtained, a compilation of all inspection reports and any noncompliance issues, a collection of testing and inspection logs, data sheets for all of the inspected components, and sign off of the special inspection team members and designer of record.

PERIODIC TESTING Periodic testing refers to testing performed over the life of a building to verify that the installed smoke -control S}'Stemshave the capability of operating as originally designed. Periodic testing includes manual testing that involves the ongoing inspection and maintenance of the smoke -control system at recommended intervals throughout the life of the building . It also includes automatic testing that may be performed at a higher frequency to verify that integral equipment is functional and operational.

Manual Testing Manual testing is crucial to ensure the long-term functionality of a smoke-control system and life safety protection afforded by that system. NFPA 92 recommends that dedicated systems be tested at least semi -annually, and nondedicated S)'Stems are only recommended to be tested annually. Dedicated systems are smoke -control systems

187

SECTION2: Building Systemsand Fire Protection Systems

and compone nts that are ins talled for the sole purpose of providing smoke control, and upon activation, these systems op era te specifical ly to perform the smoke-co ntrol functio n. Nondedicated systems are smoke-control system s and comp onents that are used to provide both typica l HVAC functions and smoke-con trol functions. Because dedicated systems will be act ivated only during a fire event or when tested, they require more frequ ent testing . Less freque nt testing requirements exist for nondedicated systems based on the assumption that pro blems are more Iikely to be detected by build ing occupants who notice a failure in the H VAC system that is used on a dail}' basis. Manua l testing should always include witnessed opera tion of all system components, usually performed by manipulating devic es (e.g., fans, damp ers, operab le doors/ windows) via the FFCP. Pri nted test report s from the automatic weekly self-testing should be reviewed to iden tify inoperable or problematic system components. For complex zoned pr essu rization smoke -contro l systems or atrium smokemanagement systems, S)'Stem documentation should be reviewed to determ ine the location of smoke -control zone bound aries in the building . The sequen ce of operat ions (in table or narrative form) shou ld then be reviewed to verify the intended operation of devices for an alar m in a given zone. Once an understanding is developed of the intend ed operation of the system , a walkdown sho uld be performed to inspect the sm oke barr iers at all of the smoke-con trol zone boundari es. The first thing to verify is whether all of the bou nda ries still exist in their intend ed locations. If a boundary has change d, it may be necessary to flag this and verify that the smoke-co ntrol system function has not been compromised . Cha nges would then have to be made to the system to account for the change in zone boundaries. Once system devices are manually verified to be operable via the FFCP, individual sequences for each smoke -con trol zone should be executed to verify that all devices align properly. This may be performed by activating a system via a smoke detector or another initiating device . For a complex smoke -contr ol system where zoned system ac tivation is provided on the FFCP, the sequence should be verified both via an initiating device and manually via the FFCP. When it ha s been ver ified that a zone is aligned according to its proper sequence, verification of press ures and door opening forces may occur via locall}' measuring the pressure and door open ing forces at multiple locations at the zone boundary, including all door s leading to the exterior or to adjacent smoke -control zones. For man)' buildin gs, pressurized stairwells may be the only smoke -cont rol systems installed in the building . For simp le constant speed pressuriza tion systems, manual test ing can be performed by simply initiating an alarm, veri.fying th at the fans opera te, and mea suring pressure d ifferentials and door opening forces at the doors. For mo re comp lex .modulating systems, care must be given not on ly to verify that the press ure differentials are in the reqt1ircd range when doors are closed, but also that fans are not programme d to overpressurize the stair when a door is held open for a prolonged period of time, as may occur during occupant evacuation.1l1is could inadvertently cause doors lo slam with the potential for occupant injury or for doors to be overpressurized to create excessive door opening forces for a per iod of time once the door is closed. Where pressurized stai rwells exist in combination with other pressurize d stairwells and/or elevator pressurization S)•stems or as part of a zoned smoke -contro l system, it is 188

CHAPTER14: Smoke-Control Systems

imperative that pressure and door opening forces be verified for all possible sequences of operations. A number of different pressure states may exist. 'fl1e stair pressurization system alone exerts one set of pressures on the stair doors. Other systems may exert additional complementary or opposing forces on doors that affect whether the pressure exceeds the required minimums or allowable maximums on the door. For modulating systems where pressure sensors are used to control fan speeds to deliver the desired pressure, sensor rnlibration must be verified during manual testing of pressurized stairwells. Sensors that are beyond their calibration date should be sent out to an accredited laboratory for recalibration. Elevator pressurization S)'Stems are tested similarly to stair pressurization systems with regard to the testing of individual pieces of equipment or the hierarchy of sequences. It is important to verify individually that elevator doors are capable of opening and closing properly when subjected to the design overpressure. 1l1e performance of an atrium smoke -control system is prinrnril)' dependent on the exhaust and supply airflows from and to the zone . 1l·1ese are verified during the initi al commissioning process by a certified TAB contra ctor. Unless an impairment to the system that may have an impact on design airflows is suspected as a result of inspect ing the fans and ductwork, it may not be necessary to perform TAD testing during every periodic test. It is often sufficient to review the printed results from the automatic self-tests, which should verify that all fans are operating within their intended range. Proper operation of all exterior doors/windows used to provide make-up air from the exterior should also be visually verified.

Automatic Testing Unlike fire alarm systems, dedicated smoke-control system components (e.g., fans and dampers) are dormant until the need arises that requires their function. Fault ed wiring or inoperative equipment adversely affecting the intended smoke-control objective may go undetected until the S)•stem is directed to operate. Electrical moni toring methods do not work for pneumatic, hydraulic, and nonaddressable equipment interoperability typically used to activate smoke-control dampers, fans, and so forth. In addition, the fans and dampers themselves are listed only according to safety concerns rather than according to reliability standards applied to fire alarm equipment. To address this concern, UL 864, Co11trolUnits and Accessoriesfor Fire Alarm Systems,incorporates a section specifically for smoke -control applications. The equipment listed for smoke-control applications carries the four letter U UKL product classification. The primary functionality provided by UUKL listed control equipment is a self-test function that allows performance testing of devices periodical!)' to provide the end -to-end verification of component functionality. TI1e requirement for performing the weeklr self-test represents the most significant recent impact on the reliability of smoke-control S)'Stems over the life of a building. UL 864 specifically requires that, for dedicated equipment, the automatic selftest function shall be capable of being performed at least on a weekly bnsis. UL 864 specifies that both audible and visual trouble signal s shall be annunciated at the FFCP identifying any function that failed to perform as intended. No specific annunciation 189

SECTION 2: Building Systemsand Fire Protection Systems

is mandated when each function operated as intended. Verification shall include posi tive confirmation of actuation, testing, manual override, the presence of power downstream of all disconnects and, through a preprogrammed weekly test sequence, report of abnormal conditions audibly, visually, and by printed report . For the weekly self-test to be performed, sensors need to be in place to enable monitoring of the performance of the component being tested . The type of sensor used depends upon the type of component being moni tored . For fans, dampers, and automatic doors/windows, the se sensors serve as the means for providing supervision of the device and meet the requirement for verification and presence of power, con sistent with th e intent of both NFPA 92A and NFPA 92B, as well as the new NFPA 92 standa rd .

Documentat ion Testing data (e.g., test procedure, measur ed pressure differentials and door opening forces, environmental conditions at the tim e of testing) should be recorded for all manual tests to provide a baseline for comparison for future manual tests. Printed logs fron1 the UUKL automatic weekly self-test should also be maintained to establish a history of component functionality during these tests. Testing documentation for all manual and automatic tests should be maintained in a location easily accessible to fire inspectors.

BIBLIOGRAPHY UL 864, Control U11its for Fire-ProtectiveSignalingSysten1s,Underwriters Laboratories, Inc ., Northbrook, IL. NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Catalog for availability of current editions of the following documents.

Co11tro/Syste111s NFPA 92, Standard.forS111oke NFPA 92A, Recommended Practicefor S111oke-Contro/ Syste111s NFPA 92B, Smoke lvlanagementSystems in 1\tfa/1s, Atria, and Lmge Areas

190

CHAPT ER

15 \.

FlRE ALARM AND CARBON MONOXIDE SYSTEMS Lee Richardson

Fire alarm and carb on m onoxid e (CO ) systems are vit al to minimi zing life and property losses durin g fires. They p rov ide early fire det ect ion, warn occ up an ts to evac uate or relocate, initi ate em ergenc y cont ro l (fire safety) functi ons, and n otify the fire depart m ent to resp ond . This chapt er provi des fire insp ection p erso nn el with an overview of fire alarm and CO system featur es and an und erstandin g of th e key in specti on p oint s n eeded to ensur e th at fire alarm and CO system in stallations are in compli an ce with applicable codes and stan dar ds. Alth ough thi s chapter highlights how to determin e th e app licable regulations th at apply and m ay, th erefor e, be helpful to plan examin ers, it assum es th at th ese regul ation s have already been identifi ed and th at th e in spec tor has been prov ided with approved plans. This chapter assum es that the inspector's role consists of (1) m akin g visual inspections of th e installation sufficient to ensure th at it compli es with both th e plans approved by th e plan examin er and the installation req uirem ents of NFPA 72®, National Fire Alarm and Signa ling Code, an d NFPA 720, Standa rd fo r the Installation of Carbon Monoxide (CO) Detection and Warning Equipmen t, and (2) witn essing satisfactory acceptance tests of th e system sufficient to ensure that the system is installed and opera ting properly. Note that any functiona l testing that is perfor med mu st be done by qu alified inspec tion and test perso nn el in accorda n ce with NFPA 72® and NFPA 720. References and inform ation in this chapter concernin g NFPA 72® are based on the 2010 edition. There are ma ny simil arities between fire alarm system s and CO systems. Althou gh m any of th e con cep ts for fire alarm system s present ed be low also app ly to CO system s, m ore spec ific in form ation on CO sys tem s is provide d at th e en d of this chapter. Refere nces an d in format ion in thi s chapte r conc ern ing N FPA 720 are bas ed on the 20 12 edi tion.

SECTION 2: Building Systems and Fire Protect ion Systems

FIREALARM SYSTEMOVERVIEW System Components In a simplified view, fire alarm systems are typica lly composed of initiating devices, notification appliances, and contro l units. Initiating devices include manua l fire alarm boxes (pull-stations), smoke detectors, heat detectors, water-flow devices, supervisory devices, and other types of detection devices that provide input signals to the system. Notificatio n appliances include horns, speakers, strobes, text displays, and other types of appliances that provide audible, visible, or tactile outputs. Control units, which are used to process input and output signa ls, can be configured as a single unit or as a combination of several units interconnected to act as a sing le system . In add ition, these units may provide outputs to operate emergency control functions (also called fire safety functions), such as fan control, smoke damper operation, and door ho lder re lease. See the Emergency Contro l Functions section later in th is chapter.

Types of Systems Fire alarm systems installed in buildings or facilities are known as protected premises (local) fire alarm systems. Protected premises are defined as "the physica l location protected by a fire alarm system" and can be a sing le bui lding or mu ltiple bui ldings (such as in a campus arrangement). Protected premises fire alarm systems are further categorized in NFPA 72® as either building fire alarm systems or dedicated function fire alarm systems. A building fire alarm system is a system that serves the genera l needs of a building or buildings and provides occupant notification or fire department notification or both. A dedicated function fire alarm system is a system installed spe cifically to perform emergency control functions where a b uilding fire alarm system is not required. The distinction between these two types of systems is made because a dedication function fire alarm system is not required to include the features that would typically be required for a building fire alarm system. For example, a d ed icated function fire alarm system may be installed for the sole purpo se of providing supervision where a sup ervised automatic sprinkler system is required. In that situation, the fire alarm system is not required to include all the features that might oth erwise b e required for a building fire alarm sys tem, such as occupant notification. Protected premis es fire alarm systems are also categorized as "requir ed" systems or "nonrequired" systems. Required systems are th ose required by other governing laws , codes, or standard s. Nonrequired systems are those in sta lled vo luntarily by the building or system owner. Co mpli an ce with NFPA 72® is required for b ot h categories . These are discussed further in the System Design Requirements section later in th is chapter.

Occupant Notification Requirements for occupant notification are genera lly established by other governin g laws, codes, or standards such as NFPA 101®, Life Safety Code®. Occupant n otification usually inv olves the provi sion of the genera l evacua tion signa l throughout the 192

CHAPTER 15: Fire Alar m and Carbo n Mo noxi d e Syst em s

building or selectable portions of the building, depending on what is required for a given occupancy. Most often, general evacuation is required throughout the entire building, but for some applications such as high-rise buildings, total evacuation is unnecessary in most cases, and partial evacuation or dire cted relocation to lower floors is permitted . The standard audible emergency evacuation signal is used for the general evacuation signal. The standard evacuation signal is sometimes referred to as the temporal-three signal and involves a repeating pattern of three ½-second pulses followed by a 1½-seco nd pause. The intention is that the standard evacuation signal be univ ersally recognized as a signal to leave the building. For some occu pancies, the building emergency response plan may allow for occupa nt rel ocat ion instead of evacuation. For these cases, the standard evacuation signal is replaced with an alert tone followed by relocation or other voice message instructions . Voice instructi ons can also be used in conjunction with the standard evacuation signal for total or partial evac uati on. Whenever partial evac uation or relocation of occupants is implemented, provisions must be made to selectively notify occupan ts in both the affected zones and in other zones. An in-building fire emergency voice/alarm communication (EVAC) system, part of the fire alarm system, is often th e m eans used to provide voice communication and/or selective occupan t n otificati on. In some applications, use of an EVAC system is specifically req uir ed by other governing laws, codes, or standards. Other governing laws, codes, or standards generally require both audibl e and vis ible signaling when occupant notificatio n is required. (Note that occ upant n otificati on may not be required for certain occupancies.) There ma y b e exemptions or allowances to omit visible signaling for certain occupancies or situations. In addi tion, th e 1990 Americans with Disabilities Act (ADA) ha s a prominent bearing on the need to have visible signalin g. The ADA Standards for Accessible D esign is contained in the Code of Federa l Regulations , 28 CFR Part 36, revised July 1, 1994. TI1isstandard has hist orica lly been used by the U.S. Department of Justice for ADA enforcement. The basis for thi s standard was the 1991 ADA Accessibility Guidelin es for Buildings and Facilities, which was amended in 2002 and was completely updated in 2004 as th e Am ericans with Disabilities Act (ADA) and Archit ectural Barriers Act (ABA) A ccessibility Guidelines for Buildings and Facilities, often referred to as the ADA/ ABA guid elin es. The m ost recent version of the guid elines has hist orica lly been us ed by the U.S. Departm ent of Tran sportation for enforceme nt of ADA . These guidelines can be ob tain ed from the U.S. Access Board. Users are ca ution ed to contact th e approp ri ate agency to determin e th e most up-to-dat e status of th e version and use of th ese documents.

Fire Department Notification Fire departm ent notificati on (also called emerge n cy forces notification) is an other feature that can be part of a building fire alarm system. Requir ements for emerg ency forces n otification are gener ally estab lish ed by oth er governin g laws, codes, or stand ards and depend on the occ up ancy inv olved . There are four means recognized by NFPA 72® to impl em ent em ergen cy forces n otification: l.

2.

An auxiliary alarm system . Centra l station (servi ce) alarm system. 193

SECTION2: Building Systems and Fire Protection Systems

3. 4.

Proprietary supervising station alarm system. Remote supervising station alarm system.

An auxiliary alarm system transmits alarm signals by interconnecting the protected premises fire alarm system to a publ ic emergency alarm report ing system (also calJed a municipal fire alarm system), where alarm signa ls are received direc tl}' at the com munications center used by the public safety agenC)' to dispatch the fire department or other emergency services. Municipal fire alarm systems are not found i11all parts of the country but are in common use in certain regions such as the Northeast . They are often characterized by the use of prominent publicaU)' accessible alarm boxes, red in color, located throughout a community, and members of the public can "pu ll the alarm" if they see a fire. The requirements for atLxiliary alarm systems are found in Chapter 27 ofNFPA 72®. The other three means used to implement emergency forces notification invo lve the use of a supervisi ng station. T11ese are often improper!)' referred to as central statio ns; however, central supervising stations are only one of the th ree types of supervis ing stations recognized by NFPA 72®. These are defin ed in 3.3.266 of NFPA 72®. The requirements in NFPA 72® for central supervising stat ion s are more extensive than those for proprietary or remote supervising stations. Central station service must be provided under contract to a subscriber and inc lude installation, testing, and maintenance of the protected pr em ises fire alarm system; monitoring of alarm, supervisory, and trouble signals; retransmission of alarm signa ls to the communication center for fire department dispatch and notification to the subscriber and authority having jurisdiction (AHJ) where applicable; runner service to the premises if needed; and associated record keeping. The provider of the central station service, the prime contractor, must be e.ither a listed central station or a listed alarm service local compan)', depending on the contract arrangement . The prime contractor must phys ically post documentation ind icating code compliance and other information about the service within 3 ft (91 cm) of the prot ected premises fire alarm contro l unit. TI1erequirements for central station alarm systems are found in 26.3 ofNFPA 72®. Although central station service is provided by a company whose commercial interest involves providing services for multiple, separately owned protected premises systems, proprietary supervising stat ions, by definition, only service facilities that are un der the same ownership as the superv ising station. TI1erequirements for proprietary superv ision stat ion alarm systems are found in 26.4 of NFPA 72®. TI1e most commonly used type of supervising station is the remote supervising station. Remote station service is most frequent!) ' provided by a company that offers commercial monitoring service for mult iple, separate!)' owned protected premises systems. However , remote station service was originally provided, and sometimes still is provided, by a municipality at a communications center that is equipped to operate as a supe rvisin g station and receive alarm signa ls through one or more of the communication methods recognized in NFPA 72® for transmission of signals to supervising stations. (This is similar in concept to a municipal fire alarm system but using communications methods addressed b)' NFPA 72®, Chapter 27.) TI,e requirements for remote supervision station alann systems are found in 26.5 ofNFPA 72®. 194

CHAPTER 1S: fire Alarm and Carbon Monoxide Systems

Communications methods for supervising station alarm systems are addressed later in the Communication i\ilethods for Off-site Notification section of this chapter.

Categories of Signals Fire alarm systems use three categories of signal s: alarm signals, supervisory signals, and trouble signals. TI1esethree categories are generally required to be kept independent of each other so that signals are not mixed. Fire alarm signals, such as a signal from a manual fire alarm box, smoke detector, or sprinkl er water -flow device , indicate the presence of a fire. Supervisory signals are signals that may indicate the inability of a fire protecti .on S)1Stem to do its job. A valve supervisory device (often called a tamper switch) of a sprinkl er system is an example of a sup ervisory signal initiating device. Troubl e signals indicate the presence ofa fault condition in a monitored circuit or component.

SYSTEMDESIGN R QU IREM NTS, A VAL, AND DOCUMENTA ION System Design Requirements TI1e requirements of NFPA 72® appl)' to the performance, installation, inspection, testing, and maintenance of all fire alarm systems, including those that are required and those that are not required. TI1e requirement to have a fire alarm system and the features it must have does not come from NFPA 72®, but from other governing laws, codes, or standards that have been adopted by the enforcing authority. TI1us, a building may be required to include a fire alarm system as a part of the features provided for the building fire protection strategy, depending on the type of occupancy. For these "required systems:' certain basic attributes of the system are usually specified as a part of the requirement to have the system. Typically included are the following: l.

2. 3. 4. 5. 6.

Requirements of the type of initiation to actuate the system (manual initiation, automatic detection, extinguishing system operation). Requirements for occupant notification. Requirements (if needed) for emergency forces notification. Requirements for the actuation of building emergenC)' control functions. Requirements related to the location of operator controls and annunciation . Requirements for the supervision of certain features by on-site or off-site personnel .

Nonrequi red systems are those that are installed at the option of the owner rather than because of a mandate from other governing laws, codes, or standards. The performance and features for a nonrequired system must be established by the system designer on the basis of the goals and objectives intended by the system owner. Nonrequired S)'Stems must also comply with the requirements in NFPA 72® even though the system is being installed voluntarily . Once it is determined that a fire alarm system is to be installed, and the basic attributes of the fire alarm system are known, the in lallat ion rules of NFPA 72® are 195

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applied. 1l1e edition of NFPA 72® that must be used (e.g., the 20 lO or 2007 edition) will depe nd on the edit ion being enforced by the local jurisdiction. 1l1is will generally be specified by the adoption reference in the applicable governing laws, codes, or stan dards. Because the terms used in NFPA 72® often have special meaning, understanding the meaning of the terms used is important to int erpret the rnles of the code properly. Many terms are common to most National Fire Protection Association (NFPA) codes and fistand standards; for examp le, the terms approved,a11thorityhavingj11risdictio11, ed. Other terms, however, are unique to NFPA 72®; for example, the terms operating mode, public and opemti11gmode, private refer to the way in which notification appli ances are used and not to publi c and private buildings. Clarity of the meaning of these terms is essentia l to proper application of the requir ements for notification applian ces for public or private mode operation .

Personnel Qualification NFPA 72® includes requirements in 10.4 for qu alification of personnel who design, install, or service fire alarm systems. The requirements for design and installation personnel reflect the need to follow state or local licensur e requirements. 'The 2010 edition of NFPA 72® also now includes personnel qualification requirements for supervising station operators.

Approval and Documentation NFPA 72® requires that the AHJ be notified prior to the installation or alteration of equipment or wiring and, if requested by the AHJ, requires that system documentation be submitted for approval. System documentation includes specifications, type of system or service, shop drawings, input/output matrix, battery calcu lations, and notification appliance circuit voltage drop calculations. Before final approval is requested, the installation contractor is required to furnish a written statement that the system has been installed in accordance with approved plans and tested in accordance with the manufacturer's published instructions and the requirements of the Code, if requested by the AHJ. A system Record of Completion is required for eveq 1 fire alarm system and must be kept up to date when any changes are made to the system . 1he Record of Completion is a multiple-page form contained in NFPA 72® that requires key information about the system to be recorded on the form. TI1e responsibility for completing the form is that of the system installer. The Record of Completion includes a sectio n on certifications and approvals for sign-olfby th e system installation contractor, system service contrac tor, supervising station contractor (if applicable), the system owner (or representative), and the AHJ. A copy of the Record of Completion must be maintained at the main fire alarm control unit or other approved location. One of the requirements of the Record of Completion form is to include copies of the Inspection and Testing form required by 14.6.2.4 of NFPA 72®. See the Inspection, Testing, and Maintenance sec tion later in this chapter. Additional documentation that is required for the system includes the owner's manual an d manufacturer's published instruction for all system equipment; record 196

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drawings; a record copy of site-specific software; and a written sequence of operation. This documentation must be delivered to the owner or representative upon final acceptance testing . The following sections high light some of th e key inspection points that shou ld be checked . Inspectors should consult NFPA 72® for additional information on specific requirements.

GENERALSYSTEMREQUIREMENTS Equipment Listing One of the fundamental requirements in 10.3 ofNFPA 72® is the requirement that all fire alarm equipment be listed for the purpose . In most cases, this means that equipment must be listed for the specific fire alarm system application for which it is used. Furthermore, equipment must be installed and us ed in accordance with the provisions of the listing and with the manufacturer's published instructions , which are usually included as the ba sis of equipment listing. Th e manufacturer's instructions should be consulted as a starting point for any listing issues that m ay arise. The listing agency and associated product listing direct ories published by listing agencies are additional sourc es to be consu lted . The insp ector shou ld confirm th at equipm ent has been in stalled and is being used wit hin the limits of its listing, including any environmenta l, performance , or application limits specified by the m anufacturer.

Fire Alarm Control Units (Panels) and Annunciation The fire alarm system ma y include one or m ore fire alarm control units . NF PA 72® do es n ot specify the location requir ed for fir e alarm control units except as may be req uir ed where annunciation functi ons are integra l to the control unit. Other gov erning law s, codes, or standards would determine whether system annunciation is re quired . The rules in NFPA 72® covering annunciation includ e a requirement that the annunciation m ea ns be readily accessible to pers onn el responding to a fire and be loca ted as required by the AHJ. Requirements in NFPA 72 ® related to annunciation ar e co ntain ed in 10.16. Aside from annun ciati on , other governing law s, codes, or standard s mi ght dictate the loca ti on of cont ro ls or require th e panel loca tion to be acceptable to the AHJ . NFPA 72® includ es requir em ents for a standard em erge ncy service int erface if re quired by th e enforcin g authority, govern ing laws, codes, or standards. These provisions intend that annunciat ors, inform ation display systems, and contro ls pro vid ed for us e by em ergency serv ice personnel be designed, arr anged , and loca ted in acco rd ance with the needs of th e organ izations int end ed to use them. The provisions are found in 18.11 of NFPA 72® with related exp lanat ion and indu stry standard provided in A.18 .11 and Annex E, respectively. Som e occupa ncies or applications, such as those for hi gh-ris e buildings, requir e th e use of an in -building fire EVAC system . Wh en these systems are used, provisions are 197

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included in NFPA 72® to address the controls and control locations (sometimes called the fire command center) for these systems. These provisions are found in 24.4.1.5. The inspector should confirm that fire alarm control units and any required annunciators or system controls are configured and located in accordance with the provisions discussed earlier and in accordance with the approved installation plans. Where more than one fire alarm control unit is provided as a part of the system design, these control units must be arranged to function as a single system. Detailed provisions for how multiple control units must be arranged and interconnected are provided in Subsecti on 23.8.2 ofNFPA 72®. NFPA 72® permits the use of combination systems-fire alarm systems that are also used for non -fire-alarm functions, such as premises security. Because of concerns that non-fire-alarm equipment may have an adverse impact on fire alarm system equipment or opera tion , NFPA 72® includes detailed provisions to prevent adverse effects. These are found in 23.8.4, including requirements that address the use of non -firealarm equipment that meets the basic voltage , temperature, and humidity performance requirements in 10.14.l and the use of non-fire-alarm equipment that does not meet thos e basic performance requirem ents. Wh ere combination systems are used, as a general rule, the fire alarm function s must always take precedence. However, when a combination system includes mass notification system functions, priority is som etim es given to thes e functions. This is reflected in the provisions of 23.8.4.5 and in th e provi sions for in-building fire EVAC systems and mas s notificati on systems in NFPA 72®, Chapter 24. A risk analysis is required to establish if and when mass notification system m essages can override fire alarm system messages . Requir ements relat ed to mess age priority, th e need for a risk analysis, and system interface are contained in 24.4.1.7, 24.4.2.1, 24.4.2.2, 24.4.2.4, 24.4.2.16, 24.4.2.25, and 24.7.7 of NFPA 72®. All fire alarm control units, includin g those that are part of comb ination systems, must be listed for thi s purpose. The insp ec tor should confirm that arrangements of multipl e fire alarm control unit s are configured prop erly to act as a single system, th at non-fir e-a larm equipm ent us ed in a comb in ation system is insta lled with th e necessary precautions to protect fire alarm system functions, and that any provisions for signal priority are clearly establish ed and related functi on s operat e accord in gly.

Fire Alarm System Protection When fire alarm control units, notification appliance circu it power extenders, or supervising stat ion transmitting eq uipm ent are installed in areas that are not continu ously occup ied, th e areas must be protected by an aut omatic smo ke detector installed at th e loca tion of the fire alarm control unit. In the conte xt of this requir em ent, the term continuously occupied means occupied 24 h ours per day, 7 days per week, 365 days per year. The provisions for this protection and related guida n ce for smoke detection coverage are provided in 10.15 and A.10 .15 of NFPA 72®, respect ively. The inspecto r shou ld confirm that any required protection has been provided and is suitab le for the environm en t in which it is located . 198

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Power Sources In general, each fire alarm system must be provided with a primary and secondary power source. The primary supply is usually the normal electrical service for the building. The secondary supp ly is often a battery system integral to the fire alarm control unit. The primary supp ly to the fire alarm system must be made through connection to a dedicated branch circuit. The dedicated branch circuit and its connections must be protected against physical damage. The disconnecting means for the branch circuit must have a red marking, must be identified with the labe l "FIRE ALARM CIRCUIT;' and must be accessible only to authorized personnel. The location of the disconnecting means must be permanently identified at the fire alarm control unit. If the secondary supply is through an external connection to the fire alarm control unit, that circuit must also be protected against physical damage. The 2010 edition ofNFPA 72® now recognizes that a properly sized uninterruptible power supply can be used in lieu of having independent primary and secondary power supplies. These provisions, as well as other provisions addressing power supply capacity, operation, installation, and performance, are located in 10.5 of NFPA 72®. The inspector should confirm that the branch circuit(s) supp lyin g the fire alarm system equipment is properly identified and protected. The inspector should also confirm that the capacity of secondary power supplies is supported by battery calcu lations demonstrat ing comp liance with 10.5.6.3.

INITIATING DEVICES Manual Fire Alarm Boxes (Manual Initiation) Manual fire alarm boxes, often called manual pull -stations, are used to initiate an alarm signal manually . Operation of a manual fire alarm box may require one action, such as pulling a lever, or two actions, such as lifting a cover and then pulling a lever (FIGURE15-1). In some institu tional occupancies, local codes may permit th e use of key-operated manual fire alarm boxes (FIGURE 15-2) . When governing law, codes, or standards require a fire alarm system to be installed and include provisions for manual initiati on of the system, manual fire alarm boxes must be locat ed throughout the protected area . Unless precluded by environmental con ditions, manual fire alarm bo xes must FIGURE 15-1Manua l fire alarm box. be red in color. They must be located

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on a background of contrasting color and be installed so they are conspicu ous , unobstructed, and accessible. Manual fire alarm boxes are required to be mounted so that the operable part is betwee n 42 and 48 in. (107 and 122 cm) above the floor level and to be placed within 60 in. (152 cm) of the exit doorway opening at each exit on each floor. Additional manual fire alarm boxes must be placed so that they can be accessed within 200 ft (61 m) of travel distance on a given floor. Where there is a group opening exceedi n g 40 ft ( 12 m), ma nu al fire alarm boxes must be located within 60 in. ( 152 cm) of each side of the opening.

FIGURE 15·2 Key-operated manual fire alarm box.

The detailed provisions for manual fire alarm boxes are contained in 17.14 of NFPA 72®. Anytime a fire alarm system is connected to a supervising station and includes an automatic fire detector or water -flow detection device, at least one manual fire alarm box is required to initiate a signal to the supervising sta tion . Th is requirement, found in 23.8 .5.1.2 of NFPA 72®, does not app ly to fire alarm sys tems dedicated to the supervision of elevator recall control and sup ervisory service in accordance with 21 .3.2. Further information and guidance on this provision are contained in A.23.8.5.1.2 ofNFPA 72®. The inspector should confirm that any requir ed manual fire alarm boxes are installed in locations in accordance with approved plans, at the proper mounting height, are accessible, conspicuous, and are not obstructed in any way.

Detection Coverage and Cross Zon ing Coverage NFPA 72® does not specify the type of coverage required for smoke or heat detection . Coverage requirements are specified by other governing laws, codes, or standards for required systems or by the fire alarm system designer for nonrequired systems. NFPA 72® include s provisions for the following types of coverage; total (complete) coverage, partial or selective coverage, and nonrequired coverage . Total coverage is typically not required by other govern ing laws, codes, or standards, unless it is being used as an option in lieu of some other fire protection feature. When total coverage is being used, NFPA 72® requires detection in virtually all spaces that are constructed of or contain combustible material. Refer to the provisions in 17.5.3.J of NFPA 72® for specific requirements and allowances. When partial or selective coverage is required by other governing laws, codes, or standards, the specific locations where detection is required are typically deta iled by these codes. Partial coverag e typically can include common areas and workspaces such as corridors, lobbies, storage rooms, equipment rooms, and othe r tenantless spaces. 200

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Selective coverage is specified to address a speci fic hazard. Refer to the provis ions in 17.5.3.2 and the related ann ex explanations in A.17.5.3.2 ofN FPA 72®. Wh en nonrequired coverage is being provided, the extent of coverage and spacing must be dete rm ined by the design er such that the goa ls and objectives set by the owner are achieved. NFPA 72® requ ires detection installed for nonrequire d coverage to meet all the requirements of the Codewith the excep tion of the prescriptive spacing require ments ofNFPA 72®, Chapt er 17. T11isis no t to say that random spacing is inten ded . TI1e in tent is to allow the use of a single detector or multipk detectors provided for spec ific protect ion, with spaci n g to meet specific fire safet)' objectives. Note that NFPA 72® req uires the design documentation for both smoke de tection and he at de tection to state th e required perfornrnnce objective rega rdless of whether the detection is being installed as requi red or nonrequired coverage .

Cross Zoning Cross zoning typi ally involves the actuat ion of two automatic detectors to a hiev an alarm response. 111isarrangeme nt is ofte n used in detection schemes for specia l hazard extingui sh ing S)'Stems to minimiz e the possibility of false activation of these systems . NFPA 72® includ es provisions for these applica tions in 23.8.5 .3. Cross zoning ca n be used subj ect to all of the followi ng limit ations, if it is permitted by the AHJ, at least two automat.ic detectors are located in each p rotecte d space, and an alarm verification feature (desc ribed later) is not used . 'foe detec tor spacing prescribed in accordance with NFPA 72®, Chapter 17, does not need to be reduced specifically for cross zonin g unless public mode notifi cat ion will be ac tuat ed . If that is the case, the spac ing must be reduced by 0.7 times the linea r spacing det er mined in accordance with NFPA 72®, Chap ter 17. ·nie alarm verification feature, defined in 3.3. 12, is provided on some fire alarm syste ms, wherein smoke detect ors report alarm co ndition s for a min imum peri od of time in order to be accepted as a valid alarm. Provisions for the alarm verificat ion feature are also contained in 23.8.5.4 and explaine d in A.23.8.5.4.1 ofNFPA 72®.

Smoke Detectors In many types of fire scenario s, detecta ble levels of smoke will pr ecede dete ctable levels of heat, and for these situations the use of smoke detectors is prom inen t. In add ition , other governi ng laws, codes, or standar ds often include spec ific requ irem ents to use smoke detection in particular occupan cies or applications. Types of Smoke Detectors. Devices for the detection of smoke can incl ud e several types of smo ke d etec tors. The most com mon is a spot-ty pe detector. Other types of smok e detecto rs includ e projected beam-type smok e detectors and air-samplin g smo ke de tec tors.

• Spot -type smoke detec tors are individual devi ces tha t usually detect smoke by means of a photoelectric senso r or ionizat ion cha mb er within the device enclosure. • Proje cted beam det ec tors are made up of either two unit s arra nged so that one uni t sends a beam of light across a space to a separate photoelectric receiving 201

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unit or a single unit that sends a beam of light across a space to a reflector and then receives the re flected beam oflight (FIGURE 15·3 and FIGURE 15·4). • Air-sampling smoke detectors draw air through an air-sampling line or lines to the smoke detec tion unit . Location

of

Smo ke

Detectors.

1he following information regar ding the location of smoke detectors is primarily for spot -type smoke detectors. For other types of smoke detectors, the Code should be consu lted for addition al rules that apply. TI1e general location requirements for spot-type smoke detectors were changed in the 2010 ed ition ofNFPA 72®. Spot -type smoke detectors must be locat ed on the cei ling or on a side wall not more than 12 in. (30 cm) fro m the ceiling to the top edge of th e det ect or (FIGURE15-5). In previ ous editions, spot-type detectors were proh ibited from being located within 4 in. (10.2 cm) of the inters ection of the ,vall and ceiling. This is still re-

FIGURE lS-3Projected beam detector.

FIGURE 1S·4Projected beam detector.

quired for spot -type heat detectors but not for smoke detectors . Note that the smoke d etec tor listing must indic ate its suitability for wall or ceiling mounting as appropriate for th e installation. NFPA 72® requires a nominal spacing of30 ft (914 cm) for spot -type smoke detec tors located on a smooth ceiling , unless a specific performance -based design criterion dictates otherwise. A tolerance of ±5 percent is suggested for consideration with the term no111i11al. For smooth ceilings, NFPA 72® also requires that all points on the ceiling have a detector within 0.7 times the selected spacing. 'TI1e term selected spaci11gis used instead of listed spacing because, unlike heat detectors, smoke dete ctors do not have a listed spacing. 1he selected spacing will generally be the 30 ft (914 cm) nominal spacing unles s the performance-base criterion specifies something else. Tirns, all points on the ceiling should be within 21 ft (640 cm) of a detector. Not e that smooth ceilings are defin ed in 3.3.33 ofNFPA 72® to be a ceiling su rface uninterrupted by continuous proj ect ions such as solid joists or beams extending down for more than 4 in. (10.2 cm) below the ceiling surface.

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Ceiling

Acceptable here

Top of detector acceptable here

Note : Measurements shown are lo the closest edge of the detector. Sidewall

?§ 1// FIGURE 1S·5 Exampleof proper mounting for smokedetectors.

Additional detailed provisions are specified in NFPA 72® for the spacing and location of spot-type smoke detectors in applications of both level and sloping joist and beam ceilings. The Codedefines solid jo .ist construction as a ceiling that has solid struc tural or solid nonstructural member s projecting down from the ceiling surface for a distance of more than 4 in. ( 10.2 cm) and spaced at intervals of 36 in. (91.4 cm) or less. Beam cons truction is defin ed as a ceiling that has solid structural or solid nonstructural members projecting down from the ceiling surface for a distance of more than 4 in. (10.2 cm) and spaced at intervals of more than 36 in . (91.4 cm). These terms apply to the rules for h eat detectors and for snwke detectors. The requirements for joist and beam smoke detector spacing have been revised extensively for the 2010 edition of NFPA 72® prescriptively to address a wide range of ceiling configurations. TI1e provisions are found in 17.7.3.2.4 and are expressed in terms of beam depth as a percentage of ceiling height and beam spacing as a percentage of ceiling height. In the application of these provisions for detector spacing, joists are treated as equivalent to beams. TI1e requ .irement s for level (nonsloping ceilings) joist and beam ceilings are con tained in 17.7.3.2.4.2 ofNFPA 72®.Level ceilings are defined as ceilings that have slope less than or equal to l in 8, corresponding to an angle of approx.imatcl}' 7.2 degrees. TI1c general rules for level joist or beam ceilings can be summarized as follows: l.

For ceilings where !he beam depth is less than 10 percent of the ceiling height, smooth ceiling spacing is permitted, and detectors can be located either on the ceiling or on the bottom of the beams.

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2.

For ceilings where the joist or beam depth is equal to or greater than 10 percent of the ceiling height, two sub-rules apply: i. Where beam spacing is equal to or greater than 40 percent of the ceiling height, detectors must be located on the ceiling in each beam pocket (in other words, each beam pock et is treated like a separate smooth ceiling) . ii. Where beam spacing is less than 40 percent of the ceiling height, smooth ceiling spacing is permitted in the direction parallel to the beams, onehalf smooth ceiling spacing in the direction perp en dicular to the beams , and detectors can be lo cated on either the ceiling or the bottom of the beam.

In addition to the general rules summarized above, specific provisi ons are included for three special cases of level ceilings: l.

2.

3.

For ceilings where b eam pockets are formed by int ersecting b eams , including waffle or pan -type ceilings, the general rule s summarized earlier for level be am ceilings apply. For corr id ors 15 ft (4.6 m) or less in width, with beam s running across the width of the corrid or, smooth ceiling spacing is permitted , and det ectors can be loca ted on th e ceilings, sidewalls, or on the bottoms of th e beam s. For rooms 900 ft2 (84 m 2) or less, smooth ceiling spacing is permitted, and detectors can be locate d on ceilings or on the b ottoms of the beams.

Th e Code also include s extensive rules to address slop in g joist and beam ceilin gs. These rul es are variations of the general rule s summ arized above for lev el ceilings. The r eade r is refer red to 17.7.3.2.4.3 through 17.7.3.2.4.6 of NFPA 72® for the d etailed provisions. The Code ad dres ses peaked or sh ed ceilings in 17.7.3. 3 and 17.7.3 .4 and require s that a detector be locat ed within 36 in. (91.4 cm) of the pe ak m eas ured hor izontall y. Additional detectors, if any, must b e space d and loca ted in accordance with th e applicable rule s for level sm oot h ceilings or level or slop ing joist or beam ceilings. Spaci ng is measured along a h orizon tal projection. The loca tion and in stallati on of sm oke detectors mu st take int o acco unt th e various ot her facto rs that can influence their performance. NFPA 72 ® provides specific rules for various conditi on s, including the follow in g: l.

2. 3. 4. 5. 6. 7. 8.

Raised floors an d suspe nded ceilings (17 .7.3.5) Partitions (17.5.2) Heating, ventilating , and air -co nditi onin g system effects (17 .7.4. 1) Plenums (17.7.4.2) Environmenta l limits (17.7.1.8) Stratification (17.7. 1.10) High -rack storag e (17.7 .6.2) High air movement areas (17.7.6 .3)

The Code also includ ed requirement s to address smoke detector s for contro l of the sp read of smoke in 17.7.5. Applic ations addressed in th e Cod e includ e: 204

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l.

2. 3.

Area detectors used to contro l the operation of doors, dampers, and ot her equipment (17.7.5.4.1) Smoke detection for air duct systems (17.7.5.4.2 and 17.7.5.5) Smoke detectors for door release service (17.7.5.6)

The Code also addresses requirements for specific types of smoke detection other than spot-type detectors including: l.

2. 3. 4.

Smoke detectors listed for door release (17.7.5.6.5 and 17.7.5.6.6) Air sampling type smoke detectors (17.7.3.6) Projected beam type smoke detectors (17.7.3.7) Video image smoke detection (17.7.7)

The inspector sho uld confirm that smoke detectors are installed in locations in accordance with approved plans and that the mounting location and spacing are appropr iat e for the ceiling surface involved.

Concealed Smoke Detectors Where a smoke detector is installed in a concealed location more than 10 ft (3.0 m) above the finished floor or in arrangements where the detector's alarm or supervisory indicators are not visible to responding personnel , NFPA 72® requires the use of remote alarm or superv isory indication. This indication must be in a location acceptab le to the AHJ. The means this indication can be through an indication at the control unit or th rough the use of separate indicator(s) clearly labeled to identify their function and installed at an accessib le location. This requireme nt was origina lly app licable on ly to in-duct smoke detectors but now app lies more broadly. The inspector should confirm that the installation conforms to the approved plans and that remote indic ators are properly located and labeled and that they operate properly.

Heat Detectors Heat Detector Types. In some types of fire scenarios, heat detection will provide the best response to the fire situation . Designs for the detection of heat can include several types of heat detectors , including the following: l.

2. 3. 4. 5.

Fixed-temperature heat detect ors Rat e-compensated fixed -temperatur e heat detectors Rate-of-rise heat detectors Combination detectors Lin e-type he at detectors

Fixed -temperature heat detectors initiate an alarm when the detect ing eleme nt reach es a predetermined fixed temperature (FIGURE15·6). During a rapid temp erature ri se, the operation of a fixed-temperature h eat detector can lag behind the actual air temperature because of th e time nee ded for the heat to penetrate the device enclosur e. 205

SECTION 2:

Building Systems and FireProtection Systems

Rate-compensated fixed-temperature heat detectors are designed to anticipate the temperature lag and provide a response closer to that of the actual air temperature (FIGURE 15·7). Rate-of-rise heat detect ors operate at a predetermined rate of temperature change. Combination det ectors can contain m ore than one elemen t to respond to a fire. Examp les of such detect ors include a combination rate -of-rise and fixed-temperatur e heat detect or and a FIGURE 15-6 Fixed-temper ature heat detector. combined smoke-and-heat detector. Typical combination detectors are il15-8 and FIGURE 15-9. lustrated in FIGURE Line -ty pe heat detect ors are typically made of heat -sensitive cable. Performance of Heat Detectors. The perfo rmanc e of heat detect ors is characterized by two ba sic parameter s: temperature classification and resp onse time ind ex (RTI). Fixed-temperature and rate -co mp en sated fixed-temper atur e he at detec tors are classified in term s of their operat ing temp eratur e in accor 15-1. Th e temp erat ur e rating of dan ce with TABLE the detector selected for a particular ap plic ation mu st be at least 20°F (11°C) above the maximum expec ted temp era tur e at the ceiling. The m aximum ceilin g temperatures for each of the given temp era ture classifications are includ ed in Table 15- 1. The performance of heat detectors includes a listed spacing, which is based on th e spaci ng that th e listi ng agen cy has used in th e testin g of th e heat detector to verify its operation and temperatur e ratin g. When heat detectors are in stalled, th e FIGURE 15-7Rate-compensated heat installed spaci ng must take int o acco unt thi s listed dete ctor. spac ing. The Code has required th at spot -type h eat detectors includ e th eir RTI and ope ratin g tempera tur e as a part of th eir listin g. RTI is a m easure of th e speed with which the heat can flow int o the detector and rai se the temp era tur e of th e heat-sensing element. RTI is a performance m etri c th at can be used

206

CHAPTER 15: Fire Alarm and Carbon Monoxide Systems

by designers more closely to predict the response of the heat detector to given fire parame ters using performancebased design methods in lieu of prescriptive spacing requ irements . 111e RTI in formatio n and marking has been required since Jttl)' 1, 2008. Detailed provisions for the performance, classification, and marking of heat detectors are contained in 17.6.l and 17.6.2 of NFPA 72®. Location and Spacing of Heat Detectors, Requirem ents for the location

and spacing of heat detector s are contained in 17.6.3 of NFPA 72®.

FIGURE15-8Combinationrate-of-riseand fixed

temperature heat detector. Location of Heat Detectors. In gen-

eral, spot-type hea t detectors must ~... . be located on the ceiling at least 4 in. (10.2 cm) from a side waU or they must ; • . ·. be located on a side wall at least 4 in. (10.2 cm) but not more than 12 in. (30 cm) from the ceiling. The proper IP' mounting lucaliun for heat detectors is illustrated in FIGURE 15-10.Tn applications where the ceiling falls und er the definition of solid joist co11strnc tion, the detectors must be mounted at .....-the bottom of the joist. In applications where the ceiling falls under the defiFIGURE 15-9Combination smoke-and-heat nition of beam co11slructio11, where the detector. beams are less than 12 in. (30 cm) in depth and are spaced less than 96 in. (2.4 m) on center, the detector is permitted to be installed on the bottom of the beam.

·. ... '

Spacing of Heat Detectors. Where the prescriptive rules of the code are being used for heat dete ctor spacing, the spacing is based on the listed spacing for th e detector. For smooth level ceilings of 10 ft (3.0 m) in height or less, the spacing must be such that all points on the ceiling are within 0.7 times the listed spacing. 1his is equivalent to spacing detectors at or within their listed spacing in genera l and at or within onehalf their listed spacing from the last row of detectors to the walls (FIGURE 15-11).If the ceiling is higher than l0 ft (3.0 rn), the spacing must be reduced in accordanc e

207

SECTION 2: Building Syste ms and Fire Protection Systems

Temperature Classificationand Color Code for Heat-Sensing Fire Detectors

Temperature Classification

Temperature Rating Range

oc

OF 100-134

Low•

Maximum Ceilin g Temperature

39- 57

OF

oc

Color Code

80

28

Uncolored

Ordinary

135- 174

58-79

115

47

Unco lored

Intermed iate

175-249

80- 121

155

69

White

Hig h

250-324

122- 162

230

111

Blue

Extra high

325-399

163- 204

305

152

Red

Very extra high

400-499

205- 259

380

194

Green

Ultra high

500-575

260-302

480

249

Orange

Source: Table 17.6.2.1, NFPA 72-2010. 'I ntended only fo r instal lation in con trolled ambient areas. Unit s shall be marked to indicate maximum ambi ent instal latio n temp eratu re.

with the adjustments specified in TABLE 15-2.Note that the code puts a limit on spacing reductions such that detector spacing is not required to be less than 0.4 times the ceiling height . For level ceilings with solid joist construction, detector spacing must first be reduced for ceiling heights above 10 ft (3.0 m), if applicable, and then reduced further by 4ln.(100mm)

121n. (300 mm) maximum

Nole: Measurements silo.ma re lo

tho osest edgeol 1he detector.

FIGURE 15-10Proper mounting location for heat dete ctors.

208

CHAPTER 15: Fire Alarm and Carbon MonoxideSystems

Heat Detector Spacing Reduc tion Based on Ceilin g Height Ceiling Height Above

Up to and Includin g

Multiply Listed Spacing by

m 0

ft

m

0

10

3.0

1.00

10

3.0

12

3.7

0.91

ft

12

3.7

14

4.3

0.84

14

4.3

16

4.9

0.77

16

4.9

18

5.5

0.71

18

5.5

20

6.1

0.64

20

6.1

6.7

0.58

22

6.7

22 74

7.3

0.52

21

7.3

26

7.9

0.46

26

7.9

28

8.5

0.40

28

8.5

30

9.1

0.34

Source:Table 17.6.3.5. 1 NFP A 72-2010.

one -half in the dir ection across th e joists. Note that in the dire ction across the joi sts, this furth er redu ction must also be applied to the spacing from the last row of detectors to the wall (d iscussed earlier for smooth ceiling spac ing) , furt her red ucing the spacing to one -half to on e-quar ter. For level ceilings with beam cons tru ction, detector spacin g must first be reduc ed for ceiling heights above 10 ft (3.0 m), if applicabl e, and then reduced by two -thirds in the direction across the beams (with a similar adju stment in the spacing for the last row of detectors to the wall). However, if the beam depth is more than 18 in. {45.7 cm) and the beam spacing is great er than 96 in. (2.4 rn), each bay formed by Solid joists Vi! beams must be treated as a separa te smooth ceiling area and detectors I spaced accord ingly. Detectors on For sloping ceilings, the same bottom of s mies app ly as for level ceiljois ts ings, except as mod ified below. Where the slop e of the ceiling is ' ' 30 deg rees or greater, the Code ½s permits the use of the average ceil_J_ ing height for spac ing of detec s = Space between detectors tors other tha n those at the peak . Wh ere the slop e of the ceiling FIGURE 15-11Arrangemen t for spot-type heat is less than 30 degrees, the Code detec tors for squa re or rectangular spaces.

,.

,.

, I.

.

I\

•

f

• t

!

209

SECTION2: lluilding Systems and Fire Protection Systems

requi res the use of the height at the peak for spacing of all detectors. In both cases, spacing is measured alon g a horizontal projection rather than along the slope. Also, in both cases, a row of detectors must first be located along the length of the ceiling within 36 in. (91.4 cm) of the peak. TI1e inspector should confirm that the type of heat detector called for in the approved plans is installed in the locations specified in these plans and that the mounting location and spacing are appropriate for the ceiling surface involved.

Radiant- Energy Detectors Requirements for the selection, location, and spacing for fire detectors that sense the rad .iant energy produced by burning substances are contained in 17.8 of NFPA 72@, Flame detectors and spark/ember detectors fa!I into this categ01y The type and quan tity of radiant energ}•-sensing fire detectors must be determined, and the performance characteristic of the detector and an analysis of the hazard must all be considered before the system is installed. The selection and application of radiant energy - sensing fire detectors are some what specialized and require an engineering evaluation of several of the conditions involved. TI1e related annex material in subsections of A.17.8 and in Annex B of NFPA 72® provides detailed explanation and guidance intended for application by qualified design professionals. It is critical that the installation conditions assumed by the designer and documented in the approved plans be verified. For these applications, a prudent designer will have already verified that the installation and perfor mance are as intended. TI1einspector should confirm that the installation conforms to the approved plans and, if possible, that th e designer is satisfied with the installation and operation.

Alarms from Suppression System Operation NFPA 72@does not require a sprinkler system to be monitored by a fire alarm system. TI1e need for this monitoring is generally specified by other governing laws, codes, or standards. NFPA 101® addresses this in 9.7.2 using the language "Where supervised automatic sprinkler systems are required by another sect ion of this code ... :' Tims, where the requirements for a particular occupancy require the use of a "supervised" automatic sprinkler S)'Stem, the provisions of 9.7.2 apply including the requirement for transmission of an alarm signal to a supervising station or a communications center. Where an automatic sprinkler system is used, the fire alarm system is often required by other codes and standards to transmit a waterflow alarm to an approved supervising station or public fire service communications center. When the automatic sprinkler system operates, the water flow-actuated fire alarm initiating device will initiate a fire alarm signal. TI1enumber of water-flow switches permitted by NFPA 72:f9on an initiating device circuit is limited to five. In a similar fashion, the need to monitor the operation of an automatic fire suppres sion S}'Slemother than water flow is addressed in 9.7.3 ofNFPA JOI® and is also often addressed in the individual suppression system standards . TI1ese suppression systems 210

CHAPTER15: FireAlarm and Carbon Mor oxide Systems

include wet chemical systems over comme rcial cooking equipment or clean agent extinguishing systems that might be used in telecom or data centers. ·when monitoring and supervision of a suppression system are required, the fire alarm system monitors the normal standby conditi.on of these extinguishing or suppression systems by means of .Ii ted supervisory initiating devices. If someone closes a sprinkler system control valve or otherwise impairs the fire protection system, the supervisory initiating device will cause the fire alarm system control unit to indicate a "supervisor>'off-normal condition." \'\'hen the off-normal condition is cleared, the supervisory initiating device will cause the Ii.realarm system control unit to indicate a "supervisory restoration to normal" signal. ·n,e number of sprinkler S}'Stemsupervisory devices permitted on an initialing device circuit is limited to 20. Special consideration must be given to the design and installation of automatic fire suppression system alarm initiating devices and supervisory signal initiating devices and their circuits, so they are not subject to tampering, opening, or removal without initiating a trouble signal. 'TI1einspector should confirm that the installation conforms to the approved plans. Confirm that alarm initiating devices (such as water-flow switches) operate to provide an appropriate alarm condition and have been tested to ensure proper performance. Confirm that supervisory devices (such as valve position switches) operate to provide an appropriate supervisory condition and have been properly tested. Refer to the test methods in 14(i) and 14(j) in Table 14.4.2.2 ofNFPA 72®.

NOTIFICATION APPLIANCES \-Vhenother governing laws, codes, or standards requi.re a fire alarm system to have occupant notification (as discussed earlier), notification appliances must be installed in accordance with the requirements of NFPA 72®. Typically, occupant notification will .involve the installation of audible and visible notification appliances {horns and strobes) throughout the protected premises to provide for total evacuation of the premises. For some occupancies, total evacuation is not practical, and an in-building fire EVACsystem is used allowi11gfor voice instru ctions to implement partial or selective evacuation or directed relocation of building occupants. Any time a fire alarm system is being used for the purpose of evacuation or relocation of occupants, NFPA 72® requires one or more notification appliances listed for the purpose on each floor of the building and located so that they have the characteristics described in Chapter 18 of N FPA 72® for public mode or private mode operation, as required. Different mi es apply depending on whether public or private mode operation is used. Public mode operation applies when signaling to occupants for total, partial, or selecti\'e evacuation or directed relocation. \Vhen permitted by local codes, private mod e operation applies for circumstances such as occupancies where occupants are not capable of evacuating themselves. Private mode operation involves signaling onl)' to person nel concerned with implementation of emergency action initiation, such as attendants or other personnel required to evacuate or relocate occupants. 211

SECTION2: Building Systems and FireProtection Systems

Audible Notification Applianc s The requirements for audible notification appliances are found in 18.4 of NFPA 72®. Audible appliances signaling in the public mode must meet the greater of the two following conditions: • Produce a sound level at least 15 dBA above the average ambient sound level. • Produce a sound level at least 5 dBA above the maximum sound level having a duration of at least 60 seconds. The term a11emgeambient sormd level, defined in 3.3.25 of NFPA 72®, involves an A-weighted measurement taken over the period of time anyone is present or over a 24-hour period, whichever time period is less. A-weighted measurements are made using instruments that account for the normal attenuations that occur in human hearing. TI1enotification appliance sound levelsspecified above are measured 5 ft ( 1.5 m) above the floor in all areas required to be served by the system. When audible notification appliances are used to signal sleeping areas, the sound levels must also be measured at the pillow level, and a third condition-a sound level of at least 75 dBA- must also be satisfied. For sleeping areas, all three conditions must be satisfied. Audible appliances signaling in the private mode must have a sound level that meets the greater of the two following conditions: a sound level at least IO dBA above the average ambient sound level or a sound level at least 5 dBA above the maximum sound level having a duration of at least 60 seconds. TI1eselevels are measured 5 ft (l.5 m) above the floor in the area to be occupied. For all applications, the code limits the combined sound level of ambient sources and appliances to a maximum of 110 dBA, measured at minimum hearing distance. Whenever the average ::imbientsound level is greater than 105 dBA, the code also requires the use of visible notification appliances. TI1eCode permits the use of listed, wall-mounted audible notification appliances or listed, ceiling-motmted audible notification appliances. \-\'all-mounted audible notification appliances that are not part of a combination audible/visible appliance must be mounted such that the top of the appliance is at least 90 in. (2.29 m) above the finished floor and not closer than 6 in. (15 cm) to the finished ceiling. Different mounting heights are permitted if the sound pressure level requirements are met for the operating mode used. Where combination audible/visible appliances are installed, the mounting requirements for visible appliances must be followed. TI1ereare no spacing provisions in NFPA 72® for audible notification appliances. However, audible notification appliances must provide the minimum sound pressure levels specified for public mode or private mode signaling as applicable. After considering the ambient sound levels, the designer of the system must decide in advance where to place the appliance based on the area to be covered and the rating of the appliance. Attenuation through doors, walls, partitions, and furnishings must be taken into account when determining appliance locations. At the completion of the installation, the system must provide the sound levels required by NFPA 72®. TI1einspector should confirm that audible notification appliances have been installed in conformance with the approved plans and that the sound levels produced have been 212

CHAPTER1S: Fire Alarm and Carbon Monoxide Systems

properly measured and conform to the minimum and maximum levelsrequired by the code. Also refer to item 15(a) of Table 14.4.2.2 in NFPA 72®. Where notification appliances (speakers) are installed for voice communications, they must be capable of reproducing voice annou ncements with voice intelligibility.Tbne signals from speakers must comply with the sound level requirements noted earlier for audible appliances. Requirements for voice intelligi.bility have been significantly updated in the 2010 edition of NFPA 72®. Specific design and installation requirements are addressed in 18.4.10. A new term, acoustically distingu ishable space (ADS), plays an important role in framing the requirements for intelligibility. An ADS is a notification zone or portion of a not ification zone that can be either a specific physically enclosed space or a space that is distinguished by certain acoustical, environmental, or use characteristics. 1l1e code requires the system designer to determine and identify ADSs during the planning and design of the system and to specify whether each ADS will require voice intelligibility. 17ie ADS assignments must be submitted for review and approval if required by the AHJ. 17ieplanning and design for these assignments should be done in onjunction with the development of the emerge11y response plan for the protected location. Note that voice intelligibility may not be achievable in some locations, such as those with very high levels of ambient noise. Other spaces may not require voice intelligibility if occupant notification is eftectively addressed for these spaces by the provisions of the emergency response plan. Note that spaces that do not require voice intelligibility are not necessarily exempt from requirements for audible signaling (evacuation or alert tones). Emergency response plan is defined in 3.3.84. Annex D ofNFPA 72® provides an extensive treatment of speech intelligibility, including many aspects of system design, acceptability criteria, and methods of testing. 17ie inspector should confirm that audible notification appliances used for voice communi cations are installed in accordance with approved plans and that voice intelligibility has been verified in the spaces where it is required in accordance with 18.4.10 ofNF PA 72®.

Visible Notification Appliances When visible signaling is required as discussed in the earlier Occupant Notification section of this chapter, it is achieved by means of visible notification appliances arranged for indirect viewing, illumination of the area surrou nding the appliance, or direct viewing of the appliance. Requirements addressing indirect viewing are addressed in 18.5.4.3, "Spacing in Rooms:' and requirements for direct viewing are add ressed in 18.5.4.4, "Spacing in Corridors: ' Indirect viewing is based on the appliances providing a minimum illumination of 0.0375 lm/ft2 (0.4036 lm/m 2). TI1is minimum i!Iumination in normal indoor environments is considered sufficient to draw the attent ion of individuals even if they are not in a position for direct viewing of an appliance. The rules for direct viewing generally assume that occupants are looking ahead and are always within direct view of an appliance. TI1eCode perm its the use of listed wall-mounted visible notification appliances or listed ceiling-mount ed visible notification appliances. TI1espacing requirements for wall-mounted visible notification appliances in rooms are provided in TABLE 15-3.TI1e 213

SECTION 2: Building Systems and Fire ProtectionSyst ems

Room Spacing for Wall -Mounted Visible Appliances

Maximum Room Size

Minimum Required Light Output [Effectiv e Intensity (cd)]

One Light per Room

Two Lights per Room (Located on Opposite Walls)

Four Lights per Room (One Light per Wall)

ft

m

20 x 20

6.l0xG. 10

15

NA

28 X 28

8.53 X 8.53

30

Unknown

30x 30

9.14 x9 .I4

34

15

NA NA NA

40 X 40

I 2.2x12 .2

60

30

15

45 X 45

13.7 X 13.7

75

Unknown

19

50 X 50

15.2 X 15.2

94

60

30

54 X 54

16.5X 16.5

110

Unknown

30

55 X 55

16.8x 16.8

115

Unknown

28

60X 60

18.3 X 18.3

135

95

30

63 x63

19.2 X 19.2

150

Unknow n

37

68 x68

20.7 X 20.7

177

Unknown

43

70 X 70

21.3x2 1.3

184

95

60

80 x80

24.4 X 24.4

240

135

60

90 x 90

27.4 X 27.4

304

185

95

100 X 100

30.5 X 30.5

375

240

95

1l 0X 110 33.5 X 33.5

455

240

135

36.6 X 36.6

540

305

135

130 X 130 39.6 X 39.6

635

375

185

120 X 120

NA: Not allowable. Source:Table 18.5.4.3. l (a) NFPA 72-2010.

spacing requirements for ceiling -mounted visible notification appliances in room s are provided in TABLE 1S-4.The pres criptive spacing provisions of these tables ensure the minimum illumination levels for indirect signaling. In locating visible appliances in rooms, it is important that the appliance be located to provide complete coverage for the room size and strob e intensity. For wall-mounted appliances, this would normally be at the center of the longest wall. TI1ese prescriptive room spacing provisions can be used for larger room sizes by subdividing the larger space into smaller spaces to achieve complete coverage for th e space in a more flexible manner. TI1e Code also includes provision s to allow the spacing of visible appliances for indirect signaling using performance-based designs in lieu of the prescriptive spacing of 214

CHAPTER 15: Fire Alarm and Carbon Monoxide Systems

Room Spacing for Ceiling-Mounted Visible Appliances

Maximum Room Size ft

m

M aximum Lens Height ft

m

Minimum Requir ed Light Output (Effe ctive Intensity); One Light (cdJ

20 x 20

6.1 X6. I

10

3.0

15

30 X 30

9.1 X 9.1

10

3.0

30

12.2 X 12.2

10

3.0

60

13.4X l 3.4

lO

3.0

75

40x40 44x 44 SOX 50

l 5.2x lS.2

10

3.0

95

53 X 53

16 2x 16.2

10

3.0

110

55 X 55

l6.8x 16.8

10

3.0

115

59x 59

18.0 X 18.0

10

3.0

135

63 x63

19.2 X 19.2

10

3.0

150

68x68

20.7 X 20.7

10

3.0

177

70x70

2Ux2

10

3.0

185

20

61

30

20x 20

1.3

6.1 X 6,1

30 x3 0

9. 1 X 9.1

20

6.1

45

44 x44

13.4x1 3.4

20

6.1

75

46x4 6

14.0x 14.0

20

6. 1

80

SOX 50

15.2X 15.2

20

6. 1

95

53 X 53

16.2 X 16.2

20

6. 1

110

55 X 55

16.8x 16.8

20

6.1

115

59x 59

18.0 X 18.0

20

6.1

135

63 x63

l9.2x 19.2

20

6. 1

150

68x68

20.7 X 20.7

20

6.1

177

70 x70

21.3 X 21.3

20

6. 1

185

20 x 20

6. 1 x6 .I

30

9. 1

55

30x 30

9.1 X 9.1

30

9. 1

75

50 X 50

15.2 X 15.2

30

9. 1

95

53 x 53

16.2 X 16.2

30

9.1

110

55 X 55

16.8 X 16.8

30

9. 1

115

59 X 59

18.0 X 18.0

30

9. 1

135

63X63

19.2 X 19.2

30

9.1

150

68 x 68

20.7 X 20.7

30

9.1

177

?Ox 70

21.3x2l.3

30

9.1

185

Source:Table 18.5.4.3. l(b) NFPI\72-2010.

215

SECTION2: BuildingSystemsand FireProtectionSystems

the tables. Performance-based designs still assume the minimum illumination levels provided in the table values. Designers are required to produce documentation supporting these designs that evaluates the polar distribution oflight output established by the appliance listing. Refer to 18.5.4.5 of NFPA 72® for the detailed requirements for this alternative approach. The Codeincludes provisions to minimize the potential effect that visible appliances might have on individuals with photosensitive epilepsy. In general, whenever more than two visible notification appliances are located in any field of view in a large room, they must be synchronized. This general rule also applies to groups of S}1nchronized appliances. Tlrns, it is permissible to have two separate groups of visible appliances in a given field of view as long as each group is synchronized within itself In general, the mounting height for wall-mounted visible notification appliances must be such that the entire lens is at least 80 in. (2.03 m) but not greater than 96 in. (2.4 m) above the finished floor. \rVhere the minimum height cannot be met because of a low ceiling height, the Codeincludes a provision to allow lower mounting. It requires mounting within 6 in. (15 cm) of the ceiling and reducing the size of the space covered by the appliance. The provisions for space reduction are addressed in 18.5.4.2 of NFPA 72®, and an example is provided at the end of A.18.5.4.1. The Code also includes an allowance for wall-mounted appliances to be at a different height if evaluated as part of the performance-based alternative permitted by the Code.TI1eheight permitted for ceilingmounted visible notification appliances is limited to 30 ft (9.14 rn) in accordance with TABLE 15-5.

Room Spacingfor Ceiling-MountedVisibleAppliances

ft

m

ft

m

20x 20

6.1 x6. 1

10

3.05

15

30 X 30

9.14 X 9.14

10

3.05

30

4Q X 4Q

12.2 X 12.2

10

3.05

60

S0x 50

15.2 X 15.2

10

3.05

95

2Q X 2Q

6.1 X 6.1

20

6.1

30

30 X 30

9.14 X 9.14

20

6.1

45

40 X 40

12.2 X 12.2

20

6.1

80

SQ X SQ

15.2 X 15.2

20

6.1

115

20 X 20

6.1 x6 .1

30

9.14

55

30 X 30

9.14 X 9.14

30

9.14

75

40 X 40

12.2 X 12.2

30

9.14

115

SQX SQ

] 5.2 X 15.2

30

9.14

150

Source:Table 4-4.4.1.1(b), NFPA1999. 216

Maximum Ceiling Height

Minimum Required Light Output (Effective Intensity); One Light (cd)

Maximum Room Size

CHAPTER 15: Fire Alarm and Carbon Monoxide Systems

Special rules apply to visible notification appliances used for signaling in sleeping areas. In general, visible notification appliances must be located within 16 ft (4.87 m) of the pillow. The intensity of the appliance must be at least 110 cd unless the appliance is mounted less than 24 in. (61 cm) from the ceiling, in which rnse it must be at least 177 ed. TI1e inspector should confirm that visible notification appliances are installed in accordance with approved plans and are at the proper mounting height, that appliance candela ratings (or settings) are as specified in the approved plans, and that proper operation has been demonstrated.

0 HER FIREALA M SYS EM

UN

N

Emergency Control Functions E mergen cy control function s (also called fire safety funct ions) are those that deal with building, fire, or other emergencies intended to increase the level of life safety for occupants or to control the spread of the harmful effects of the fire or other hazard . Emergency control functions are addressed in Chapter 21 of NFPA 72®. These func tions include the following: elevator recall; elevator shutdown; control of smoke dampers, motorized fire dampers, fans, smoke barrier doors, and fire doors; door release; and door unlocking. Requirements for two new emergency control functions have been introduced in the 2010 edition of the Code: first responder use elevators, and elevators for occup ant -controlled evacuation . The need to incorporate a particular emergency control function(s) is established by other governing laws, codes, or standards such as NFPA 101® or by codes and standards for the systems involved such as American National Standards Institute/ American Society of Mechanical Engineers (ANSI/ASME) Al 7.l/CSA B44a, Safety Codefor Elevatorsn11dEscalators,or NFPA 90A, Sta11dardforthe J11srallatio11 of Ail'-Co11ditio11ing a11dVe11tilati11g Systems. 1l1e inspection and testing of emergency control functions have historically not re ceived the attention they should . 1l1e requirements in NFPA 72® for inspection and testing of these functions are found primarily in 14.2.6 and item 23 of Table 14.4.2.2. Often, the testing of these functions involves testing personnel from multiple dis ciplines and therefore requires a significant effort to coordinate and document thi s testing properly. In addition, the extent of testing of the emergenq' control function is arguably not well defined in NFPA 72®, and the testing requirements of the equip ment standards that govern the performance of the emergency control function are not as well correlated with NFPA 72® as they could be. These issues have recently been more clearly identified, and future editions of NFPA 72® and other related equipment standards will be more closely coordinated and defined. A related new document, NFPA 3, Recom111e11ded Practice011Co111111issio11ing and IntegratedTesti11g of Fire Protectio11and Life Safety Systems,otters guidance on how best to handle the coordinated testing of these interrelated systems. In the meantime, verification that emergency control functions have been properly inspected and tested will require special attention of the inspection authority, building owner, and all related disciplines. Ultimately,

217

SECTION2: Building Systems and Fire Protect ion Systems

the inspector should verify that systems that interface with the fire alarm system have been demonstrated to operate properly in response to outputs of the fire alarm system. This can be done through a complete end-to-end test or a series of overlapping tests coordinated and documented to ensure that the interconnected systems operate as intended. It is of utmost importance to verify the interconnected systems are left in their final operational condition-that nothing is left disconnected or bypassed.

Suppression System Actuation The requirements for suppression system operation are contained in other codes and standards . However, if au tomatic or manual activation of a fire suppression system is to be performed through a fire alarm control unit, the control unit must be listed for the releasing service. Specific requirements for suppression system actuation are contained in 23.13 ofNFPA 72®. Each space protected by an automatic fire suppression system actuated by the fire alarm system must contain one or more automatic fire det ectors . 'These fire detectors must be installed to sense the fire condition and subsequently initiate the sequence to allow the suppression system to discharge its agent. Also refer to the earlier Detection Coverage and Cross Zoning Coverage section for additional information. In gener al, the Code requires suppression systems or groups of systems to be controlled by a single releasing service fire alarm control unit that monitors the associated initiating device(s), actuates the associated releasing device(s), and controls the associated agent release notification appliances. If the specific provisions of 23.13 .9 of NFPA 72® are met, multiple control units can be used if the configuration of those control units is listed for releasing service. If the releasing panel is located in a protected premises having a separate fire alarm system, it must be monitored for alarm, supervisory, and trouble signals by-but not be dependent on or affected by-the operation or failure of the fire alarm system of the protected premises. Special provisions are included in 14.2.5 ofNFPA 72® to ensure that suppression systems are not inadvertently discharged during the testing of the associated fire alarm system. These provisions as well as those of23.13 should be carefully observed, and the inspector should confirm that the system design and installation complies with these provisions and with the approved plans.

Communications Methods for Off-site Notification Fire department notification (or emergency forces notification) is most often accom plished through the use of a supervising station alarm system. An overview of the different types of supervising stations and how requirements for emergency forces notification are established was provided earlier in the Fire Department Notification section. The discussion that follows focuses on the types of communications methods addressed in the code for transmitting signals from a protected premises to a supervising station. The communications methods for transmitting signals to a supervising station are addressed in 26.6.3 of NFPA 72®. The code includes "General" requirements 218

CHAPTER15: Fire Alarm and Carbon Monoxide Systems

in 26.6 .3.1, which are performance based and app ly to the "newer" technologies that are not otherwise specificall}' addressed in 26.6.3.2 or 26.6.3.3. Newer techno logies cur rently availab le include tran smit ters using Internet Protocol (IP) transmitting over the Internet or private IP facilities and transmitters using various (non -dial -up) digital cellular tech nol ogies. The code includes prescriptive requirements specifically to address digital alarm communicator systems in 26.6.3.2 and radio systems (two -way radio frequency multiplex S}'Stems and one-way private radio alarm systems) in 26.6.3.3. Wired IP transmission can be "integrated IP" or "native IP" (integral to the fire alarm control unit - not need ing further conversion equ ipment) or it can involve additional convers ion equipment or modules to allow interface with more traditional transmitters such as digital alarm communicator transm itters (DACTs). 'Tilese conversio n modules are some tim es called IP communicators (in various forms), are considered to be part of the fire alarm system, and must be listed as such. In either case, the rules in 26.6.3.1 app ly. 111eoutput of the IP communicator is typically connected to an Internet access device such as a cable modem or to a local area network with access to the Internet. 111epremises communicat ions equipmenl' downstream from the IP communicator is not pa rt of the fire alarm S}'Stembut is still required to be listed as general comm unica tion s equipment. In addition, this downstream commu nications equipment must be provided with 24 hours of secondar}' power capacity. 111ecode does not current!}' address the means to provide this capacit}'. Commu nicat ions equipment installed under the provisions of 26.6.3.l must annunciate failure of the communications path at the supervising station within 5 minutes of the failure. A digital alarm communicator system invo lves the use of a DACT locat ed at the protected premises and a digital alarm communicator receiver usually located at the supervising station. Two commu nications channels are required between the trans mitte r and receiver. 111efirst channel must use the public switched telephone network (PSTN) . The second channel can be a second line (number) of the PSTN or it can be one of six other communications methods listed in 26.6 .3.2.1.4. 111ereq uired connection of a DACT to a PSTN has historically meant connec tion to a plain old telephone service line-a pair of copper wires connected to the telephone central switching cen ter. However, over the years, the telephone companies have used field-deplo}'ed multiplexing equipment to increase system capacity and, more recently, for conversion to nontraditional methods for tran sm itting voice signals. Many cable communications companies have begun also to offer telephone serv ice using nontradition al methods for transmitting voice signa ls. The 2010 edition ofNF PA 72® includes an update to the definition of PSTN that recogn izes a broader categor}' of network s facility-based voice 11et111orks (MFVNs). 111is term is defined using the term 1m111nged in 3.3.141, and the related annex material in A.3 .3.141 explains what these systems are and the performance expected from them. A DACT must be connected to the PSTN upstream of any private telephone system at the protected premises. These connections mu st be under the control of the subscriber. 111econnec tion must be made to a loop start, not a ground start, telephone circuit. 111istelephone lin e is not required to be a dedicated line. In accordance with the testing methods specified in NFPA 72®, the response time from the point of actuation of the initiating device at the protected premises to the 219

SECTION2: Building Systems and Fire Protection Systems

receipt of the signal at the supervising station must not exceed 90 seconds. However, the rules for DACT operation permit a sequence of attempts for successful transmis sion that can greatly exceed 90 seconds. Despite these allowances for DACT transmission, the statistical probability of a successful DACT transmission occurring well within 90 seconds (on th e first attempt) is very high. The inspe ctor should determine the type of communications method that has been used and confirm that it has been properly installed and is operational. If an MFVN is being use d for a digital alarm communicator system, it should be confirmed that the service provider meets the expectations iden tified in A.3.3.14; otherwise the networ k should not be considered an IvIFVN. If an IP communicator is being used, it should be verified that th e equipment is listed for fire alarm system use and has been installed in accordance with the manufacturer's instructions and the code. Particular attention needs to be given to ensure that any (11011-fire-alann system) premises -located communications equipment is provided with a sour ce of seco ndary power in accordance with 26.6.3.1.1 2. It should be confirmed that proper operation of the communications channel has been verified in accordance with item IS(a) of Table 14.4.2.2 in NFPA 72®.

FIREALARM SYSTEM WIRING REQUIREMENTS The installation of fire alarm system equipment, including wiring, must comply with NFPA 70®, National Electrical Code®. Article 760 of NFPA 70® addresses fire alarms systems and specifies requirements for non-power-limited fire alarm (NPLPA) and power -limited fire alarm (PLFA) circuits. PLFA circuits are distinguished from NPLFA circuits by the equipment listing. TI1e equipment marking or listing must indicate the power-limited feature or source. The wiring methods permitted for the power source of NPLFA circuits must comply with the requirements of the NFPA 70® 2008 edition, Chapter s 1 through 4. The wiring methods for NPLFA circuits that are outlined include the use of the various wiring methods addressed in NFPA 70®, Chapter 3, and the use of multiconductor NPLFA cables. The wiring methods permitted on the supply side of PLFA power sources must also comp ly with the NFPA 70® 2008 edition, Chapters l through 4. NFPA 70® permits the use of either NPLFA wiring methods and materials or the use of PLFA methods and materials on the load side of a PLFA power source. NFPA 7()® places limitations on the mi.x.ing of cables and con ductor s used for fire alarm systems. Specific rule s are provided for both NPLFA circuits and for PLFA circuits. TI1ese rules preclude the mixing of NPLFA circuits with PLFA circuits. TI1ey also restrict other combinations, especially with non-fire-alarm applications. TI1ere are also rules in NFPA 72® that have an impact on fire alarm system wiring. NFPA 72® includes requirements for pathways (circuits) to be designated as Class A, Class B, Class C, Class D, Class E, or Class X depending on their performance. The perfo rm ance for these class designa tions is specified in 12.3 of NFPA 72®. Class designat ions are generally determined by the fire alarm system designer based on consideration of various factors that may affect the reliability needs of the S)1Slem. NFPA 72®

220

CHAPTER 15: Fire Alarm and Carbon Monoxide Systems

also specifies requirem ents for fire alarm circuit performan ce in 23.5, 23.6, and 23.7 for initiatin g device circuits, signa ling line circu its, and notification appliance circuits, respectively. Class A and Class X circuit designations both requi re redundant pathways . Although both of these classes must continue to operate past a single open, Class X is also requir ed to operate past a single short circuit. Class A and Class X circ uits must be run so that the outgoing and return condu ctors of the circuit are routed separa tely. The code does include allowances for the latter under certai n conditions as specified in 23.4.2.2. Jn addit ion, Nf PA 72® requires circuits to be monitored for integrity. The intercon necting conductors of the circuit must be monitored so that the occurrence of certain fault condi tions such as a single ope n or single ground-fault condit ion causes a trouble indication. As a result, connections for each device or appliance must be made so that the opening of any connection causes a trouble signa l. Looping the conductor around the device or appliance terminal :md then continuing to the next device or ap pliance can result in an unsatisfactory connection. Listed devices and appliances that are provid ed with duplicate terminals for each circuit connection must be terminated by cutting the wire and making each connection separately. The correct wiring method 15·12.T11eincorrect method is dem for pigtail connec tions is demonstrated in FIGURE 15·13. onstrated in FIGURE A wiring technique called "T-tapping ;' the parallel connection of one or more devic es or appliances at the middle of a circuit, is also forbidden for all initiating device and notification appliance circu its. It is permitted for Class B signaling line circu its if per mitted by the designer and equipment listing. As a point of underst anding, initiating devic e circuits are those that have no means of identifying the initiating device that operated it. Signaling line circ uits are able to carry multiple signals and can identify the device or other equipment sending the signal. Addressable systems use signaling line circuits. Additional NFPA 72® requirements that can have an impact on wiring are the requi rements for system surv i.vabili.ty.T11esereq uirements .involve the design, protection, Wire nut

FIGURE 15·12Correct wi ring method for pigtail connections.

221

SECTION2: Building Systemsand Fire Protection Systems

Wire nut

Installed device

FIGURE 15·13Incorrect wi ring method for pigtai l con nect ions.

and layout of circuits to support continued operation during a fire. NFPA 72® includes designations for pathway (circuit) survivability in 12.4. Different wiring protection provisions are specified for Pathway Survivability Level 0, Level I, Level 2, and Level 3. Requirements to use particular survivability levels are provided in 24.3. 5 for each of the different emergency communications systems addressed in the code. In-building fire emergency voice/commun ications systems used for partial evacuation or relocation and two-way telephone systems are requ ired to have Level 2 or Level 3 pathway survivability. TI1einspector should confirm that fire alarm system wiring has been installed in accordance with approved plans, using methods appropriate for the designated circuit class and survivability levels. It should be confirmed that no inappropriate T-tapping has been used and that Class A circuits are routed in accordance with 23.4.2.2. The proper use of the system (trouble indications) in response to fault conditions should also be verified .

OTHER WARNING EQUIPM ENT Smoke Alarms versus Smoke Detectors Chapter 29 of NFPA 72® addresses fire warning equipment including single- and multipl e-station smoke alarms and household fire alarm systems. A smoke alarm is distinguished from a smoke detector by the fact that the smoke alarm is a single unit that prov ides detection and a warning signal all in on e unit. A smoke detector involves detection on!)' and requires the use of a fire alarm control unit and separate not ification appliances as a part of a fire alarm system to complete the warning function. 222

CHAPTER 15: Fire Alarm and Carbon Monoxide Systems

Residential Requirements Other governing laws, codes, or standards specify requirements for smoke alarms in one- and two-family dwellings and other residential t)'pes of occupancies. Often, these codes will also recognize the use of a fire alarm system to fulfill the functional requirements specified for the smoke alarms. 1l1isallowance is also recognized in 29.5 of NFPA 72®. For some residential types of occupancies, such as multifamily dwellings, other govern ing laws, codes, or standards may specify requirements for a building fire alarm system with additional provisions for smoke alarms (or smoke detectors of a household fire alarm system) in specific locations in the dwelling unit. 'TI1eseadditional provisions may specify that the smoke alarms (or smoke detectors of a household fire alarm S}'Stem) sound onl}' within the individual dwelling or living unit aud not actuate the building fire alarm system unless otherwise permitted by the AHJ. Note that requirements for the building fire alarm system occupant notification also include signaling to the dwelling or living units. Sound -level requirements for notification appliances must also be met in these spaces, espe ially in I ping areas. It is important to consult other governing laws, codes, or standards for clarification about the specific requirements for the occupancy. Household fire alarm systems are required to have two independent power sources consisting of a primary source that uses a normal building service and a secondaq 1 source that consists of a rechargeable battery that can operate the system for at least 24 hours in the normal condition followed by 4 minutes of alarm. Smoke alarms are required to be powered from a normal building service along with a seco11dar>7power source capable of operating the device for at least 24 hours in the normal condition followed by 4 minutes of alarm. Alternately, smoke alarms can be powered by a nomepla ceable primary battery that is capable of operating the device for at least 10 years followed by 4 minutes of alarm, followed by 7 days of a trouble signal indicating that there is an ongoing S}'Stemfault. Und er certai n conditions, local codes may allow the use of smoke alarms powered by only a replaceable 1-year battery. NFPA 72® allows the use of these types of smoke alarm only when specifically permitted by other governing laws, codes, or standards.

Smoke Alarm Installation Smoke alarms (or system smoke detectors) must be installed in locations that comply with the locations specified in other governing laws, codes, or standards. NFPA 72® includes requirements for specific detector locations in 29.5.1. The excerpt below provides basic location requirements. Refer to the additional provisions of 29.5.1 for additional detection requirements including requirements addressing larger dwellings. 29.5.1 * Required Detection. 29.5.1. J* Where required by othergoverningJaws, codes, or standardsfor a specific

type of ocwp(llrcy,appro1ed single- n11d11111/tiple-stntio11 smoke alarms slw/1 be installed asfollows: 1

223

SECTION 2: Building Systems and Fire Protection Systems

(l) *Jn nil sleepingroo111s and guest rooms

(2}*011tsideof ench separatedwellingunit sleeping area, within 21ft(6.4111)ofn11y door to a sleepingroo111, with the distance 111ensured n/011gn path of tm\le/ (3) 011every le,,elofa dwelling unit, including bnse111e11ts (4) 011every lel'eiof n residential board nnd cnre ocwpnncy (smn/1facility), including base111e11ts a11dexcludingcrawlspacesand w1fi11ish ed attics (5) [11the lil'ingnren(s) of a guest suite (6) In the living area(s) of a residentialboard and rnre occupancy(smallfacility) In addition to the general siting requirements found in 29.5.l, specific location requirements are provided in 29.8.3.4. TI1ese requirements are primarily intended to ensure proper performance for smok e alarms (or S)'Slem smoke detectors) and include location restrictions to minimize nuisance alarms. These restrictions are important, be ause frequ ent nuisa nce alarm s ca n cause occupants to disconne ct or remov e alarm s. Chief among these is a new provision in the 2010 Code restricting any type of smoke alarm from being installed within IO ft (3.0 m) of a fixed cooking appliance. The specific provision for this restriction is shown in this excerpt of 29.8.3.4:

(4)*Smokenlnrms and smoke detectorsslm/1not be instnlled within nn area of exclusion determined by a 10ft (3.0 111)radial distance nlo11gn horizontalflow path from a statio11a,yor fixed cookingappliance,unless listedfor installationin closeproxi111ity to cookingapplim1ces.Smoke alarms and smoke detectorsinstalledbetween 10ft (3.0 m) and 20ft (6.1 111) nlo11gnhorizontalJ7owpathfrom n stntionmy orfixed cookingappliance shall be equippedwit/1a,1alarm-silencingmeans or usephotoelectricdetection. Exception: Smoke alarms or smoke detectors thnt use photoelectricdetection shall be permitted for installation at n radial distancegreater than 6 ft (1.8 111) from nny stationary orfixed cookingappliance when thefollowi11gconditionsare met: (a) 11-ie kitchen or cookingarea and adjacentspaces hnve 110 clearinferiorpartitions or headers and (l,) 71,e10 ft (3.0 111)area of exclusion would prohibit the placement of a smoke alarm or s111oke detector requiredby other sections of this code. The related annex material in A.29.8.3.4( 4) provides diagrams and additional guid ance to explain these provisions. The provisions in 29.8.3.4 also restrict smoke alarms from being installed closer than 36 in . (91.4 cm) from a bathroom door (if the bathroom contains a tub or shower) or from supply registers of forced air heating or cooling systems or from the tip of the blade of a suspended ceiling fan. Provisions are also included to address conditions such as high or low temperature, humidity, or sources of smoke that can lead to nuisance alarms. Chapter 14 ofNFPA 72® requires the replacement of smoke alarms located in oneand two-family dwellings within 10 years of the date of manufacture. Note that this rule does not apply to system smoke detectors. 224

CHAPTER1S: FireAlarm and Carbon Monoxide Systems

The inspector should confirm that smoke alarms are installed in all required siting locations and that the specific installation provisions in 29.8.3 of NFPA 72® be followed. It is especially important that exclusion areas in 29.8.3.4(4) be observed .

Carbon Monoxide Detection and Warning Equipment NFPA 720 is derived in large part from NFPA 72® and makes extensive use of extracts from NFPA 72®. [n many cases, the provisions in NFPA 720 are the same except that the terminology is tailored to CO detection instead of fire. Where extracted material has been modified in this way, brackets are used in the t xt to id ntify the change. Extracted paragraphs are annotated with extract references in brackets (e.g., [72:10.3.l]) at the end of each paragraph. Where there is no extrac t reference provided, the provisions are unique to NFPA 720. CO detectors are the primaq• initiating devices for NPPA720. There are three types of sensor technology used in CO detectors made today: biornimetic, electrochemical, and semiconductor. Biomimetic sensors simulate the reaction of hemoglobin to CO by darkening in color- a change that can be detected photo -electricall)'· Electrochemical sensors use an electrolyte to generate electric current, which changes in proportion to CO exposure. Semiconductor sensors are heated and, when exposed to CO, exhibit a higher resistance that can then be measured. All three types of sensors have a limited lite (usuall)' less than 10 years) depending on the technology used, and must be replaced in accordance with manufacturer's instructions. CO detection systems ca n bt: separate systems or can be combined with fire alarm systems. Combined systems can take advantage of sharing componen ts of such notification appliances and result in a cost savings; however, note that there are some basic differences in system requirements. For CO systems, the secondary power supply is required to have a capacity that supports the operation of notification appliances for 12 hours rather than the 5 minutes required for fire alarm S)'Stems.1he 12-hom requirement can be reduced to 5 minutes if the system is monitored by a supervising station and an appropriate emergency response (as specified in 7.2.2 of NFPA 720) is provided . Occupant notification can be limited to the area where the CO alarm was initiated if CO alarm signals are also transmitted to a constantly attended on-site location or off-premises location. Otherwise occupant notification is required throughout the premises (similar to fire alarm systems). The need for retransmission of a CO alarm signal from the supervising station to the fire department or commu nicat ions center is dependent on whether the emergency response agency requires it. 'The superv i.sing station should have a notification plan in place for each monitored premises that includes multiple points of contact with the subscriber. Regardless of whether CO alarm signals are retransmitted to the fire department or communications center, the supervising station is always required to contact the responsible party(s) in accordance with the established notification plan. 225

SECTION2: Building Systems and Fire Protection Systems

Requirements for the location of CO detectors in commercial applications are provided in 5.8.5.3 of NFPA 720. A partia l excerpt including related explanatory annex material is provided below:

5.8.5.3 Req11ire111e11ts for Cnrbo11J\fonoxide Detectors. 5.8 .5.3.1 Cnrbo11monoxide detectors slwll be i11stnlledns specified i11the mmHijac-

trirer'spublished i11structio11s in nccordm1cewith 5.8.5.3.1(1) and 5.8.5.3.1(2), or 5.8.5.3.1(3); (l) 'On Jheceilingi11the same mo111 as per111a11e11tly i11stalled.f11el-b11mingapplia11c es (2)*Ce11tmll y located 011e11ery habitable level and i11every HVAC zone lf the building (3) A pe1fom1n11ce-/Jased design i11accordancewith 5.8.5.3.2 A.5.8.5.3.1 (1) Detectors are located 011 the ceiling above permane11tlyinstalled fuel -Imming appliances because of the buoyancy of the heated combustion gases ns comparedto normal ambient temperatures. Detectorsshould be locatedas closenspmc ticnl to the permanently installed.fi,el-burningapplianceconsistentwith considerations of detectoraccessibility,sourcesof detectorconta111i11ation, and m1isnncesources.Siting co11sidemtio11S can i11cludetmnsimt backdmfting spillageof flue gases during startup and ventilationsupply or exhaust vents. A.5.8.5.3.1 (2) The purpose of detectors centrally located on every habitable level

is to detect the migration of rnrbo11monoxide _ji-0111 pernw11ently installed ji1elb11rni11g appliances and other sources of carbon monoxide. Other sources of rnrbon monoxide can include vehicles or other eq11ipmentthat uses nn internal co111bustion engine, bnrbeq11egrills, propane operated eq11ip111e11t, and systems used to genemte hydrogen. Detector location and spacing should be based 011an engineering e11n luntion tlrat considers potential s011rcesnnd migration of cnrbon monoxide. HVAC systems shortld be considered in tire locating of rnrbo11111onoxidedetectors becartse the HVAC systems provide a good means of mixing and tire migration of carbon 111onoxide.Other considerations when lorn ling cnrbon monoxide detectors nre areas with closed doors and rated de111isi11g walls, which can isolate or separate areas within HVAC zones. Add itional information for tire location of rnrbon monoxide detectors is a11ailablein the Fire Protection Resenrch Foundation (FPRF) tech11icalreport Developmen t of a Technical Basis for Carbon Monoxide Detector Siting. NFPA 720 also includes an allowance for performance-based detection designs . CO detectors are requ ired to be marked in accordance with their listing and have their detect ion thresholds set to respond at the levels specified in ANSI/UL 2034, Sta11-

dnrdfor Single and Multiple Station CarbonMonoxide Alarllls. CO alarms are different from CO detectors in much the same way as smoke alarms are different from smoke detectors, as discussed above . CO alarms are required to be listed to ANSI/UL 2034, Sta11dnrd for Si11gleand i\tfu/tipleStation Carbon

Monoxide Alarl/ls. 226

CHAPTER 15: Fire Alarm and Ca,bon Monoxide Systems

Requir ements for the location of CO alarms are provide d in 9.4. l of NFPA 720. A part ial excerpt including related explanatory annex materia l is provided below: 9.4.1. l* Carbo11111011oxide alarms or detectorsshall be installedasfollows:

(l) Outside of each separate dwelling 1111it sleeping area in the i111111 ediate vicinity of the bedrooms

(2) 011eve,y ocwpia/Jle level of a dwelli11g1111il , i11c/11di11g base111e11ts , exc/11di11g nttics mid crawlspaces (3) Other locations where required by applicablelaws, codes,or sta11dards 9.4.1.2 * Each alarm or detector shall be located 0 11 tile ll'all,ceiling, or other location as specified i11the 111a11ufacturer's published i11strnctiomthat acco111pa11y the 1111it. A.9.4.1.2 The locationfor effective pe1for111ance is 110/ generallydependent 011 111ou11ti11 g height. 'flw density o.lcarbon monoxide is similar lo that of air at room tempera-

ture, a11dcarbon 1110110:

'j;

X

iii 3

V,

X

X

Inspect all tubing associated with releasevalves Test solenoid release of master release valve

X

Test manual releaseof master releasevalve

X

Test operation of slave valves

X

Reset all pneumatic cylinder releasevalves

X

Checkposition (open, closed) unsupervised

5'

lCl V'>

-0

X

X

Test on-off cycling of valves intended to cycle System control valves

Annu al Ot her

Testpressuremaintenancevalves(unloaders)

Test start/stop pressure sett ings for standby pressure Pneumatic valves

co

~a:

X

Checkposition (open, closed) supervised

X

Check pressureconditions at all valves

X

Control equipment

Testoperation of solenoid valves

X

Test setting on Unloader Valves

X

Test setting of PressureRelief Valves

X

Test back-flow prevention devices

X

Test funct ionality of releasingpanel

X

Test programmable logic controller

X

Testautomatic releasing mechanisms

X

Test manual releasing mechanisms Inspect detector circuits, detector locations, pull-stat ions

X X

Test detector system zoning and functionality

X

Testpressure& flow switches

X

Test troub le (supervisory)signals

X

Test remote and local alarms Water mist Inspect nozzle locations, potential obstructions system piping & Inspect piping, supports nozzles Inspect nozzle screens,strainers

Enclosure features, interlo cks ventilation

Inspect enclosure integrity

X X X X

X

Test interlocked systems (e.g., ventilation shutdown)

X

Test shutdown of fuel/ lubrication systems

X

After discharge test

n

~

l>

'ti -I m :,:,

... co ~

~ :;:

:a· VI

';;; N 00

(.;.)

;;; ~

SECTION2: Building System, and Fire Protection ':,ystems

Detecto rs

To open nozzles

Master valve

Releasing panel

Water supply

0 Water cylinders 1. Stee l base and frame 2. Compressed gas cylinder (driving medium) 3. Cylinder control valve 4. Pressure switch, supervise cylinder pressure 5. Burst disc 6(a). Soleno id opera ted master release valve 6(b). Pneumatic release valve 7. Micro-leakage valve 8. Pressure switches , alarm ii system trips 9. Vent por t, for filling wate r cylinders

Gas cylinder

10. Primary system or section al control valve 11. Test connection and drain 12. Test orifice (alternative to full discharge) 13. Cylinder discharge header with filling port 14. Cylinder rack with restraints 15. Pressure-rated water cylinders with dip tube 16. Optional load cells to monitor wa ter cylinders 17. Water supply valve, normally closed 18. Filter and hose with adap tor fill ing for filling cylinde rs

FIGURE 18-1Hig h-pressure, gas-driven system w ith stored wate r (pre-eng ineered system).

press ure and volume of gas stored in the C)'linder. Comp ressed gas cylind ers are avail able in a varie ty of heig ht s and diamete rs. TI1e correc t cylinder specifica tions must be provided in the system documentation. It is possible for a purchaser to ord er the wrong compressed gas q 1 linder, either in terms of volume or pressure . It should be ob vio us if the wrong size ofc)'li nder ha s been installed beca use the cr lind er head valve will not be at the corr ect he ight to con nec t to the flexible tubi ng . Howev er, it is less obviou s when the press ure in the cylinder is no t correct. Comp res sed gas cylinder s are purch ased locally from commercial suppli ers (no. 2 in Figure 18- 1). D iffere nt countries have differ en t pr essure rat ings for cylinders. In Europe, Asia, and Australia, 2900 -psi (200 -bar) cylinders are standard. In North Am erica, com mercially available cylinde rs are typ ically 2250 psi ( 155 bar). It is impo rtan t to check the actual crlinder pressure whe never a new q 1linder is installed. O ne would th ink that in Nort h America, where compressed gas cyl ind ers are typica lly pressurized to 225 0 psig (155 bar ), an installation with fill-in pla ce cylinders would be designed to be pre ssurize d to 2250 psig (155 ba r). Howe ver, becau se th e equ ipm ent had been d esigned for a global mark et, inclu di ng Ind onesia an d Australia, it was intended to be pressurized to 2900 psig (200 bar) . The duration of protection would not be ach ieved at a lowe r

284

CHAP ER 18: Water M ist System s

To open nozzles

Delec lors

Conlrol panel

SlaX

lve

~

eumallc interconnectmn

r - -- - - - -- --

f

---- - -- ' --

4

cp

Master valve ~ ••-

••

-

9. _

••

Waler cylinders

Gas cylinder

1. Solenoid operaled masler release valve (wilh local manual releas e) 2. Pneumatic lubing inlerconnec ling ·master· lo "slave· valve 3. Discharge header

Water cylind ers

Gas cylinder

4. Pneumatically activated slave valve (no local manual release) 5. Pressure switch. alarm when system trips 6. Cylinder rack with restrain ts 7. Compres sed gas cylinders (driving medium)

FIGURE 18-2High -pressure, gas-drive n system w ith mult iple units connected for sequential or simultan eous discharge.

starting pressure and initial volume of gas. This is th e type of detailed information that need s to be comm unicat ed lo the inspe ctor and the maintenan ce people.

Water Cylinders Water cylind ers are distin ct from water tanks. They are m o dified gas cylind ers, some times provide d with an inter ior lin ing for corro sion pro tec tion and with a special head assembl y to permit refilling i11sitri. Refilling is do n e via a vent port (no. 9 in Figure 18-1). 'foe cylind er is known to be full when water starts to flow out of the open vent ports in adjacent cylinde rs. Only an experie nced technicia n should per form the filling operatio n. A perman ently moun ted water supply (no. 17) with filter and hose valve (no . 18) shou ld be mounted near the unit to provide a sour ce of dean, filtered water. On ce the cylinders are filled and the ven t port s sea led, there is no way visually to confirm tha t water storage q 11ind ers are full of water. Some end users mandat e the use of load cells to monitor the weight of the cylinders . 1his is the best way to supervise the water level. Regardless of whether the u nit is inspec ted weekly or annually, it is not possi ble to confirm the presence of waler in the qdinde rs without either open ing the vent plugs or using load cells to monitor weight.

285

SECTION2: Building Systems and Fire Protection Systems

Delect ors

Contro l panel

;~::i

( ·'·\

h .

Air vent Level switch Sight glass

17 f-- --

f

--++I_.

!

11 ...,_.__._,__~~-'-"'--4 Slave Slave Slave Master Compressed gas cy linders (atomizing medi um)

~ ~ ~

Water supply strainer , and drain 1. Stee l base and frame 2. Compressed gas cylinders (atomizing medium) 3. Cylinder control valve 4. Pneumatic cylinder release valve 5. Pressure supervisory switch with burst disc 6. Solenoid opera ted mas ter release valve 7. Manu ally opera ted mas ter release valve 8. 112'' high pressure tubing man ifold 9. Air pressure control valve (high to low pressure) 10. Air-actuated globe valve (cycle air line)

11. Airline to twin- fluid nozzles (low pressure) 12. Waterline to twin-fluid nozzl es (low pressure) 13. Air-actuated globe valve (cycle water line) 14. Low pressure solenoid valves (for opera ting air-actuated globe valves) 15. Manual release valve (opens globe valves) 16. Pressure gauge , pressure relie f valve and ven t valve 17. Low pressure rated water tank 18. Drain and re-fill connection with straine r

FIGURE 18·3 Low -press u re, twin -fluid, compressed gas-driven system.

LOW-PRESSURE,TWIN-FLUID, COMPRESSEDGAS-DR IVEN SYSTEMS WITH STORED WATER Twin-fluid, compres sed gas- driven system s use water and comp ressed gas in two separate piping streams, which are joined at the nozz le to generate water mist. A low-pressure , gas-driven system using tanks for storage of water combine d with high-pr essure compressed gas q 1linders and a pressure-regula ting valve is show n 286

CHAPTER 18: Water Mist Systems

in FIGURE 18-3. The water storage tank is connected to a bank of compressed gas cylinders, with the compressed gas used to drive the water out of the tank and into the distribution piping. The pressure at the entry to the water storage tank is regulated to provide a sustained pressure on the system nozzles for as long as the gas supp ly lasts. Pressure in the water storage tank and the distribution piping is typically less than 290 psi (20 bar).

INTERMEDIATE-PRESSURE,SINGLEFLUID, COMPRESSED GAS-DRIVEN SYSTEMSWITH STORED WATER In intermediate-pressure, single-fluid, compressed gas-driven systems, the compressed gas is used solely to drive the water out of the tank and into the distribution piping. Unlik e in the high -pressure systems, the water and air pressure that ente rs th e tank and piping in an intermediate-pressure system is regulated so that tank pressure does not exceed a certain value, generally less than 500 psi (34 bar) (no . 8 in FIGURE 18-4). The discharge pres sure at the nozzl e is maintained at an approximate ly constant level until the supply of water or compressed gas is depleted. There are therefore both high- and

Detectors

Control panel

~

1. Compressed gas cylinder 2. Steel frame and cylinder restra ints 3. Cylinder co ntrol valve 4. Pneumatic cylinder release valve 5. Pressure switch with burst disc 6. So lenoid operated mast er release valve 7. Manually operate d master release valve 8. Pressure regulating valve, high to low

9. Air-line tubing 10. Pressure switch , alarm on discharge 11. Primary system control valve 12. Strai ner on discharge line 13. Water line to nozzles 14. Water level indicator (dipstick) 15. Water tank rated for intermediat e-pressure 16. Drain and refill co nnection with strain er

FIGURE 18-4 Low- o r intermediate -pressure, sing le-fluid, comp ressed gas- driven syste m.

287

SECTION 2: Build ing Systems and Fire Protect ion Systems

low-pressure components in the hardware. The system controls include air cylind er valves, regulating valves, solenoid valves, and a fire alarm and control panel.

TESTING PRE-ENGINEERED GAS-DRIVEN SYSTEMS Gas-driven water mist systems sim ilar to those shown in the previous four figures are referred to as pre -engine ered systems. Each set of water cylinders and compressed gas cylinders can supply only a fixed number of n ozz les, with a maximum permitted length for each size of tubing. These systems are sometimes assembled with several se ts of water and compressed gas cylinders conn ected in a "master-slave" arrangement (see Figure 18-2) . For example , the "master" cylinder may be released by a solenoid valve upon a signa l from the detecti on system releasing panel. The "slave" cylinder valve will b e activated pneumat ically by a pr essurized line from the "master" cylinder. If mu ltiple banks of water and compressed gas cylinders are dischar ged simu ltaneously, the numb er of noz zles that can be supplied is incr ease d. If disch arged sequentially, multiple units extend the duration of protection, for example, from 10 to 20 minutes. The pneumatic tubing connecting ma ster and slave va lves (for simu ltaneous release) is seldom or nev er sup ervise d (no . 2 in Figure 18-2). For that reaso n, pneumatic valves should be inspected carefully for possible problems with the control tubing. Generally, it can be determin ed to functi on properly only at th e tim e of an annual trip test of th e system.

End of Discharge During discharge testin g of decaying pressure gas-dr iven systems, it is difficu lt to id entify the end of discharge because the noise and mist generati on do not stop abrupt ly, as the y do when a pump is shut off. The end of disch arge can b e id entifi ed as th e tim e at which th e pressure at th e remote nozzle falls below th e minimum specified op eratin g pressure for the n ozzle. The minimum operating pressure for a hi gh-pre ssure, singlefluid , gas -driven system , h owever, is n ot the sam e as th e minimum opera tin g pr essure for a n ozzle on a pumped system. The system docu mentati on should specify th e minimum pres sur e th at indicates the end of a 10-minute disch arge.

PUMP-DRIVEN WATER MIST SYSTEMS Wat er mi st system s using a pumped water suppl y represent a categ ory of"e ngin eered" wat er mist systems . Pump-driv en systems may be low, int ermed i ate, or high pressure. "Low" pr essure water mist systems m ay be a misnom er, because m ost so -called low -pressure water mist systems usua lly n eed m ore pressur e th an is delivered from conventi onal rated fire pumps . Although th e minimum pr essure n eeded for th e n ozzle m ay b e at or b elow 175 psig (12 bar), most of th e pipin g system and th e pump disch arge mu st be higher th an 175 psi g (12 bar), whi ch is the int erm ed iate pressur e 288

CHAPTER 18: Water Mist Systems

Detectors 15

0p )(

14

Releasing panel

~

,--A--,

7

• (laboratory) semiannually the first year, then annually thereafter if the water quality is consistently acceptable over the course of the first year. 1

295

SECTION2: Building Systemsand Fire Protection Systems

FULL DISCHARGETES The annual full discharge testing of the water mist system is intended to verify the operation of all components, from the detection system to the releasing valves and regulators. Only the manufacturer' s representative should undertake this testing. A full discharge test is the best way to confirm the performance of al.I components, including duration of discharge and timing cycles. Only by flowing water through the actual distribution system and nozzles can one be sure that both the water supply and the compressed gas pressure are sufficient to sustain the desired duration and that water is delivered to the nozzles at the required pressure. ·n1e owner needs to provide the opportunity to conduct this disruptive test.

MODIFIED DISCHARGETEST Although water -sensitive equipment can be covered by plastic, for various reasons it is not always possible to conduct a full compartme nt discharge test of every water mist system. Provided that a full discharge test was conducted at the time of the acceptance testing of the new system, it could be acceptable to conduct a modified discharge test during the periodic annual testing. A modified discharge test could be conducted by means of a test connection designed to simulate the hydraulic demands of the system. Orifice disks installed on separate water and air lines (in a twin -fluid system, for example) and piped to a suit able location could be used to simulate the actual flow rates. Test connections for such purposes are not always a standard feature. A number of the first water mist systems to be installed did not include test conne ctio ns. If the difficuli-)' of conducting effective annual tests creates problems for the ongoing maintenance of the system, test connections should be retrofitted to piping.

CYCLING SYSTEMS Some wate r mist systems intended for small machinery spaces were designed to dis charge water in intervals in order to reduce the amount of water required. Thus, for example , the system would discharge water for 40 seconds, then stop for 20 seconds; and repeat this sequence for 10 minutes. TI1isconcept was adopted in order to obtain 10 minutes of protection, as required by the flv1 Global fire test protocol and ap proval document, with only a 7- or 8-minute volume of stored water and compressed gas. The principle relies on "enclosure effects" to be effective. Fire in a sealed engine room or turbine enclosure will generate heat and will increase the temperature in the enclosure. As water is discharged, a percentage of mist is evaporated. When the discharge stops, the fire may not yet be extinguished and will regrow, again raising the temperature and increasing the amount of water vapor in the environment. After four or five cycles, there may be enough water vapor present to reduce the mcygen concentration to below 15 percent, sufficiently low to extinguish some hydrocarbon fires. The process relies absolutely on confining both heat and water vapor in the enclosure. TI1e risk is that a fire will regrow in the "off" interval, involve more fuel,

296

CHAPTER 18:

Water Mist Systems

do more collatera l damage to control wiring or other cri tical elements, and perhaps reach an intensity that is beyond the capability of the mist system to control. Further more, the complexity of the control valves needed to stop and start the flow of water and compressed gas on closely timed intervals iucreases the possibility of a malfun ction occurring in some device. Some ind ustrial end users such as ExxonMobil will not allow cycling water mist systems. This author conducted an acceptance test involving full system discharge of a cycling water mist system on the North Slope of Alaska. Pressure tran sducers were installed to measure the ystem pres ure in both water and pneumatic lines over the full six cycles that were supposed to achieve the 10 minut es of protection; however, the pressure data showed thaL only five of the six interva ls were at the proper nozzle pressure-both water and air pressures durin g the sixth inter val were below the m i.nimum. Witho ut having conducted the instrume nted full system discharge, no one would have been able to tell that the system was not capable of achieving its requ ired pressur during the final inter val. As a pre-engineered gas-driven system, it was necessary to expand the gas cylinder rack to add cylinders . TI1e situation was highly problematic given that the equipme nt had been fitted into a small space with no room for expansion.

DISCHARGE IME A 30-minute minimum discharge time is specified by NFPA 750 for almost all situations, although "hvo consecutive discharges of 10 minutes duration" is accepted for pre-engineered systems. Systems that use a compressed gas source with stored water must store a large enough quantity of each fluid (water plus compressed gas) for the anticipated duration. Any evaluation of the system in future years must be able to show that the system discharge duration can be met. Periodic inspection and testing of all functional elements of the water mist system are recommend ed in Table 18-3.111ese include the sectional control valves, drains, flow switches and alarm devices, piping, hangers, and nozzles. Procedures for such inspection or testing are similar to those for other types of fire protection systems. Practices described in NFPA 72® and NFPA 25 should be followed. TI1ere are several unique aspects of water mist systems that should be highlighted.

SECTIONAL CONTROL VALVES It is particularly important to test the sectional control valves used in large water mist systems (see 110. l 5 in Figure 18-5 and no. 11 in Figure 18-6). TI1esevalvesare electrically activated. Compared with standard fire protection valves,they are of a nonstandard valve design. TI1eyma}' be nonind icaling; how to operate them manually may not be clear. Even during a trip test, it is not possible to tell by visual inspection whether they are fully or partially open. On high-pressure systems, friction loss through sectional control valves may be very high. To keep friction losses within reasonable bounds, the total flow lo a system may be divided among two or more sectional valves in parallel. TI1issituation introduces

297

SECTION2: Building Systems and Fire Prolection Systems

the possibilitythat one of the valves in the group could fail to open and cause the hydraulic performance of the S)'Stem to be adverse!)'affected.The only way to test sectional control valves is to open them under full pressure and flow water. The inspector must study the documentation carefullyto determine how the valvesare intended to operate. In facilities where a full discharge test can be conducted annually, the performance of sectional valves can be tested. If it is not possible to do a full system discharge, an alternative means of testing the functionality of the valvesmust be found. One possibility is to select nozzles in a limited area where water can be discharged without damage, and then to flow water through a limited portion of the overall system. Alternatively, design the system so that there is a test line on each individual zone in a water mist system on the downstream side of ea h sectional control valve. If a sectional control valve on a dry-pipe or deluge system does not "seat" properly, water may leak past the valve and begin to fill the overhead piping. On a large deluge system with high ceilings, the leakage will not be noticed until water starts to "dribble" out of the nozzle. In Alaska, where water leaking past the control valve would freeze and destro)' the piping system, a means of monitoring for leakage should be provided. A leakage trap is installed 011 the discharge side of each sectional control valve. Any leakage slowly fills a drum -drain until there is enough to be sensed with a liquid level sensor. A trouble indication can then be given in the main control room.

NOZZLES 'Nater mist nozzles must be protected against plugging by use of filters and screens. Annual checking and cleaning of screens or filters are important. Manufacturers have nozzles with different K-factors, orifice diameters, and orifice patterns. A single system may use more than one type of nozzle. It is extremely important that the person who removes nozzles for inspection, or possibly replaces nozzles for whatever purpose, knows what characteristics each nozzle must have. Information on the type of nozzles and where they are installed is contained in the system documentation . As indicated earlier, the srstem documentation is the foundation for ongoing maintenance and inspection. TI1emaintenance personnel must know what types of nozzles were installed in the facility and should perform the following inspection: Ensure that correct types of nozzles are installed. Ensure that thermall)1 activated nozzles with glass bulbs have the correct temperature rating for the location. 3. Remove several nozzles and inspect the condition of screens and O-ring seals. 4. Ensure that structura l members or stored materials will not obstruct the discharge patterns. 5. Ensure that nozzle orifices are not becoming plugged with external grime. 6. Ensure that nozzle dustcaps (if used) are in place and that they dislodge as required upon activation of the S)'Stem. l.

2.

298

CHAPTER 18:

Water Mist Systems

DETECTION EQUIPMENT, CONTROLS, INTERLOCKS,AND ANCILLARY EQUI MENT Vlith the exception of water mist systems that are sprinkler equivalents and use thermally activated (automatic) nozzles, water mist systems rely on a separate detection system to activate. Inspection and testing procedures therefore must include the detection system . 'The type of detect ion is often dictated by the listing for the system. For example, turbine enclosures and machinery space systems listed by FM Global are requir ed to use thermal detectors as a minimum . Neverthe less, most machinery space systems in oil industry facilities on the North Slope of Alaska use triple infrared flame detection . The listing also indicates that certain shutdown events must be S)'nchronized with the release of the S)'Stem. TI1eventilation system should be shut down, door holder s released, dampers closed, and lubrication or fuel lines shut off. Ir is essent ial to have a "cause and effect" matrix chart to identify how the interlocks and ancillar)' shutdowns work. TI1eannual testing of a water mist system must confirm the proper operation of all events associated with release of the water mist S)'Stem. A written record of all inspection, testing, and maintenance activity on a system should be kept with the system documentation. NFPA Codes, Standards, and Recommended Practices See the latest version of the NFPA Catalog for availability of current editions of the following documents.

ofStntionmy Pwnpsfor FireProtection NFPA 20, Stm1dnrdfor the J11stnllntion NFPA 25, Stn11dnrdfor the Jnspectio11, Testing,and Mai11fe11a11ce of Water-Bnsed Fire ProtectionSystems NFPA 70®, National Electrical Code® NFPA 72®, National FireAlarm and SignalingCode NFPA 750, Standard 011 WaterMist FireProtectionSyste111s

299

CHAPTER

19 SPECIALAGENT EXTINGUISHING SYSTEMS GeraldR. Back III

TI1e most widely used special agent extinguishing systems discharge carbon dioxide, halogenated agents, dry chemicals, or wet chemicals. Description of other clean agent extinguishing systems (i.e., halocarbons and inert gases) and additional information on wet chemical systems used for commercial cooking operations can be found elsewhere in this text. Special agent systems typically have the following components: detection and control equ ipment, agent release devices, agent storage containers (agent cylinders), agent distribution systems (pipes, hoses, and nozzles), and ancillary devices such as door closures and damper releases. Most of these systems are available as either engineered or pre -engineered systems. An engineered system is one in which individual rnlculations and designs are required to determine the agent flow rate, the size of the piping, noz.zle pressures, and so on. A preengineered system, sometimes called a package system, is one in which minimum and maximum parameters have been predetermined and confirmed by an independent test ing laboratory. Installation within the listed limits ensures adequate flow rate, pressure, and pattern coverage without the need to perform flow calculations. Most installations will be classified as pre-engineered systems designed for a specific hazard. Because these systems discharge a fixed agent quantity, it is important that all hazards are adequately protected. Changes in the hazard, such as the layout of the equipment being protected, modification to the enclosure surrounding the hazard, and changes in the type of fuel, could affect the system's ability to extinguish a fire. As a result, the inspection/maintenance company should assess whether the system is code compliant and that the design meets the listed parameters prior to entering into an agreement to inspect and maintain the system. It is also recommended that the S}'Stemdesign be reviewed on a regular basis to verify that it is still code compliant and designed within the listed parameters.

CHAPTER 19: Special Agent extinguishing Systems

DESIGN TYP S Special agent systems can be catego rized into one of three basic t)1pes: tota l floodi ng systems, loca l application systems, and hose line systems. Many of these systems are extensio ns/add -ons to larger tota l flooding systems .

Total Flood ing Systems Total flooding systems d ischarge an extingu ish ing agent into an enclosure lo provide a u niform fire extinguishing conce nt ratio n throughout the entire enclosure. Ope nings in th e enclosure somet imes can be compensa ted for b)' p rovidin g au tomatic clos ure device s or by adding extinguish ing agent. Although Halon 1301 is no longt!r prod uced, there are sl ill ma ny systems curre ntly in use th at ut ilize the agen t.

Local Appli a i n yst ms Loca l applicat ion systems clischarge th e agen t d irect ly onto the hazard witho ut relying on an enclosure to reta in the agent. Local .ipplication systems are t)•pically used to protec t cooking equipmen t, vehicles (e.g., engine compartme nts of buses), large construction equipmenl (e.g., eng ine spaces/compa rt ments of compactors, excava tors, dozers, dump tru cks), pr inting presses, dip an d quench tanks, spray boo ths, oil-filled electri c transforme rs, and so 0 11. Around the beg in ning of the 2 I st century, mos t resta urnnl kitchens were protected with local -applicat ion dry chemical extingu ishing systems. However, because of the use of new cooking o ils and higher temperatures in the cooking process, dry chemical exting uishi ng systems are no longer adequa te for this appl icatio n (because of th eir lack of cooling). Repla cement systems, suc h as wet chemical or other water -based agents, are n ow the indus try standard. An examp le of a loca l-app lication wet chemica l restaurant system is shown in FIGUR E19-1. Local-application wet and dr y chem ical agent exlinguishing systems are now bei ng used to p rotect the engine compar tments of mass transpor tation vehicles and large conslru ction equipm ent. J\fos t of these systems are dr y chemica l because of the lower temp era tur e ranges th at th ese systems need to operate in. An example of a dr y chemica l co nstruc tion veh icle engi ne compartme n t fire ext ingu ishing system is shown in FIGURE19-2.

Manual Extinguishing Systems (Hose Reels) Hose line S}'Stems consist of a sup ply of ext inguish ing agent, such as carbon d ioxide, Halon 12 11, or dry chemical, and one or more hose lines that allow ma nu al de livery of the agent to th e fire (FIGURE19-3). Tl1e hose lines are connec ted to the agent co ntainer eith er d irectly o r by mea ns of interm edia te pip ing. In many cases , these hose reels are add -ons to larger total flood ing or local app lication systems.

301

SECTION2: Build ing Systemsand FireProtection Systems Duel

Hood

Manual Actuator

~

~

Nozzle (typ.)

Agent Storage Cabinet

Range

Fryer

Grill

FIGURE 19-1Typical wet chemical kitchen range, hood, duct, and fryer fire protection system.

INSPECTION AND MAINTENANCE Special agent extinguishing systems are required to be inspected semiannually by a trained professional. The manufacturer, installing contractor, or any other qualified organization can provide regular service contracts. Upon completion of the onsite inspection and maintenance visit, a report summarizing the work, the findings, and recommendations (e.g., potential upgrades and changes in maintenance procedures) should be filed with the owner. The owner should also be trained to perform routine inspections . Most National Fire Protection Association (NFPA) codes require a visual/physical inspection of the system on a monthly basis. The service company should review the key areas of the system that need to be inspected each month. Examples include accessibility to the activation devices, detector status (cleanliness and damage), nozzle status (cleanliness, damage, nozzle caps, and positioning), piping status (physical damage), and agent cylinder status (damage and pressure) . The tables given in this chapter outline the main aspects of the i.nspection and maintenance procedures and should be used for guidance only. For more details on these procedures and the requirements associated with a specific system type/design, refer to the applicable NFPA standards at the end of this chapter and to the manufacturer's system/design manual. Jn addition to inspecting the system and the protected haz ard, personnel that could potentially operate the system (e.g., the kitchen staff of the

302

CHAPTER19: Special Agent Extinguishing Systems

Agent Distribution Hoses

ellent Cartridges

Control Module with Manual Actuat or Remote Manual Actuator

FIGURE 19·2Dry chemi cal construction vehicle fire protecti on system.

restaurant or the operator of the vehicl e) should be briefed on both the manual and automatic ac tivat ion devices/loc ation s and proce dure s.

Carbon Dioxide System Inspection and Maintenance A number of properties make carbon dioxide a desira ble fire extinguishing agent. Namely, it does no t react with most substa nces, it d oes not conduct electricity, it prov ides its own dischar ge pressure, and it does not leave a residu e. Carb o n dioxide extinguishes a fire by reducing the oxygen concentration at th e fire location below th e value needed to sustain combustion (i.e., it smothers the fire). Local-app lication carbon d ioxide systems ca n also have a cooling effect as the agent is discharged d irect ly on the hazar d.

Safety Considerations. Extinguishin g conce ntrat ions of carbon dioxid e can be fatal. 111erefore, carbon dioxid e total floodin g srs tems should not be used in normally occu pied spaces. To preven t accidental discharge, a "lockout " is provided wh en persons not familiar with the operation of the system are present in the protected space . Authorities respo nsible for con tinu ity of fire protection mu st be notified of the lockout and 303

SECTION 2: Building Systems and Fire Protection System s

subsequent restoration of the system. For total flooding hazards that are normally unoccupied but in which personnel might be present for maintenance or other purposes, there must be some means to warn the occupants of an impending discharge. This requires an alarm and a time delay to ensure evacuation prior to agent discharge.

Type of Storag e. The carbon dioxide supply can be stored in high- or low-pr essure co ntainers. High -pr essure containers [-850 psi (5860 kPa)], usually cylinders, are designed to store liqu id carbon dioxide at ambient temperature. Because the tempe ratu re affects the pressure, it is important to store the cylinder in an area where temperature s will be within the listed limits. Low-pressure containers [-3 00 psi (2068 kPa)] are pressure vessels designed to maintain the temperature of carbon dioxide at about 0°F (18°C) by means of insulation and refrigeration.

Inspection and Maintenance. The main points of the inspe ction and maintenance procedure for carbon dioxide systems are listed in TABLE 19-1. Refer to NFPA 12, Stn11dnrd011 Car- FIGURE 19-3Carbondioxide hose reel ban Dioxide Extinguishing Systems, and to the extinguish ing system. manufacturer's system/design manual for more complete information. Inspection and maintenance should be carried out by qualified/ trained personnel.

Halogenated Agent System Inspection and Maintenance Halogenated extinguishing agents, or halons, have a number of unique fire protection qualities. In addition to their ability to extinguish flames, they leave no residue to clean up after a fire, and they do no t cause thermal shock to delicate equipment. The two halons most widely used in North America are Halon 1301 [bromotrifluoromethane (CF 3Br)] and Halon 1211 [bromochlorodifluoromethane (CF 2CIBr)]. Halon fire extinguishing agents have been linked to stratospheric ozone depletion and are no longer produced. However , many halon systems are still installed/in use and must be inspected periodically and maintained.

Safety Considerations. Experience and testing have shown that personnel can be exposed to Halon 1301 and Halon 1211 vapors in low concentration for brief periods 304

CHAPTER 19: Special Agent ExtinguishingSystems

Testingand Inspection Guidelines for Carbon Dioxide Systems Verification or Test

Minimum Frequency

Owner

Overallphysicalappearance

Every30 days

Accessto activation devices Detector status Nozzlesstatus Pi ing status Cylinderstatu Service/Maintenance Organization

I. Initial physical inspection

Every6 months

Accessto activallon devices Detector status Nozzlesstatus Piping status Cylinder status Changesin the hazard

2. Supervisedcircuits

Everyyear

3. Control panel (all functions)

Everyyear

4. Powersupply

Everyyear

5. Emergencypower

Everyyear

6. Detectors(test, c;lean,and check wiring)

Every6 months

7. Verificationof the time delay

Everyyear

8. Alarms(operation,warning signs properly displa> 'ears

17. Hydrostatictesting of high-pressurecontainers

12years;after a discharge if more than 5 yearssince last test

18. Liquid level gauge of low-pressure containers

Every week

Note: Forall of theseverifications and tests,the actuating controls must be removed from the agent containers to avoid accidentaldischarge.

\... 305

SECTION 2: Building Systems and Fire Protection Systems

without serious risks. However, unnecessary exposure is not recommended. Exposure to high concentrations- IO percent for Halon 1301 and 4 percent for Halon 1211- can present a health hazard to personnel. Halon 1211 should not be used as a total flooding agent in enclosures that are normally occupied.

Type of Storage. Total flooding systems can have a modular design or a central storage design. In modular systems, a nozzle is connected to a halon container with little or no piping. J\foltiple containers are located throughout the space to be protected so that the concentration of the agent will be uniform upon discharge. In central storage systems, halon containers are connected to a manifold, and the halon is delivered to discha rge nozzles through a piping network. Inspection and Maintenance. The main points of the inspection and maintenance procedure for halogenated systems are listed in TABLE 19-2.Refer to NFPA 12A, StnnSystems, and to the manufacturer's system/ dnrd 011 Halon 1301 Fire Exti11g11ishi11g design manual for more compl ete information. Full insp ect ion and maint enance should be carried out by qualified/trained personnel.

Dry Chemical System Inspection and Maintenance Dqr chemical extinguishing agents are referred to as either ordinary dry chemicals or multipurpose dry chemicals. TI1eformer are used to combat fires involving flammable liqu ids (Class B) and electrical equipment (Class C). The latter are effective on ordina r y combustibles (Class A), on flammable liquids (Class B), and on electrical equipment (Class C). Typical dry chemical agents include sodium bicarbonate, potassium bicarbonate, monoammonium phosphate, and potassium chloride to name a few. Dry chemical extinguishing agents should not be confused with dry powder agents, which were developed for use on combustible metals. Extinguishing agents used on combustible metal fires are discussed elsewhere in this text. Ordinary dry chemical is used primaril) ' to extinguish flammable liquid fires. As a result, there are numerous applications for these systems including engine compartments of mass transportation vehicles and large constrnction equipment. With the exception of the detection system, vehicle extinguishing systems are very similar to nonvehicle-based systems . Dry chemicals are not recommended for deep-seated Class A fires and are not suitable for fires in materials that supply their own oxygen for combustion. In addition, dry chemical systems are not recommended for protecting delicate electronic equipment. Some dq 1 chemicals are corrosive (e.g., monoammonium phosphate) and should be removed from all undamaged surfaces as soon as possible after extinguishment.

Safety Considerations. The discharge of dry chemicals can create hazards to personnel by reducing visibility and temporarily making breathing difficult.

306

CHAPT ER 19: Special Agent Extinguishing Systems

esting and Inspection Gu idelines for Halogenated Agent Systems

Verifi cation or Test

Minimum Frequency

Owner Overall physical appearance

Fvery 30 days

Access to activation devices Detec tor tatu s Nozzles statu Piping status C~11inder status

Service/Maintenance Organ izat ion 1. Initial physical in~pectio n

Every 6 months

Access to activation dev ices Detector status Nozzles status Piping status Cylinder stat us Changes in the hazard 2. Detection and actuation system

Every 6 months

Detectors checked and cleaned Supervision features checked Ope ration of actuat ing contro ls (removed from contai ners) Operation or manua l operating controls 3. Containers Visual examination

Every 6 mo nt hs

Verification of agent quan t ity and pressure

Every 6 mon ths

4. Piping and nozzles Visual verification for any evidence of co rrosion or obstruct ion and prope r position and alig nmen t of nozzles

Every 6 months

Vi ual inspectio n of hoses

Every 6 mo nt hs

Hydrostatic testing of hoses

Every 5 years

5. Auxiliary equipment

Every 6 months

Note: For all of these verifications and tests, the actuating contro ls must be removed from the agen t conta iner~ to avoid acciden tal di s harge.

307

SECTION 2: Building System s and Fire Prot ect io n System s

Type of Storage. Dry che mic als are stored in pressure vessels (cylind ers) either at atm osp heric pressure until th e system is actuated or at the pressure of the internally stored expe llant gas .

Inspection and Maintenance. The main points of the inspection and maintenance procedure for dry ch em ical systems are listed in TABLE 19-3. Refer to NFPA 17, Standard for Dry Chemical Extinguishing Systems, and to the manufacturer's system/ de sign manual for more complete information . Fu ll inspecti on and maintenanc e should be carried out by qualified / trained personnel.

Wet Chemical System Inspection and Maintenance A wet chemica l extinguishing agent is typically a soluti on of dry chem ical agen ts dissolved in a liquid (typically water). Wet chemica l systems are used to combat the same fire ha zards as dry chemica l systems but provide additiona l coo lin g to prevent reigniti on . Some common wet chemica l agents includ e aqu eo us potassium carbonate, aq ueo us sodium bicarbonate, aqueous monoammonium phosphate, and aqueo us potassium chloride . Wet chemical solutions are primarily used to extingu ish flammable liquid fires such as fuels, oils, and greases. The liquid contained in th e wet chemica l agent provides cooling of the fu el surface and surround ing mat erials reduc ing the likelih oo d of a reignition. For grease fires (e.g., deep fat fryer fires), the wet chemica l may mix /reac t with the grease to form a soapy layer over the oil surface of flammable liquids (a process called saponification) . Wet chemica l extingu ishing agents are typi cally n ot used to protect Class A hazards and are not suitable for fires in m ateria ls that supply th eir own oxygen. Because wet chemical soluti ons are electrically conductive, wet chemical agents are not recommended for protecting electronic eq uipm ent. In additio n, most wet chemi cal solut ions are corrosive and sh ould be washed from all undamaged surfaces as soon as possible after discharge/extinguishment.

Safety Considerations. The mist produced during the discharge of a wet chemica l agent can be an inh alation h azard to personnel (the chemicals are m ore of an irrit ant th an a toxin) . Type of Agent Storage. Wet chem ical agents are typically stored in pressurized cylinders.

Inspection and Maintenance. The main points of th e inspect ion and maintenance 19-4. Refer to NFPA 17A, Stan procedure for wet chemica l systems are list ed in TABLE dard for Wet Chemical Extinguishing Systems, and to the manufacturer's system/ design manual for more comp lete information . Full inspection and maintenance shou ld be carried out by qualified/trained personn el. Fo r kitchen app lications, specia l attenti on needs to be placed on cleaning the detection system elemen ts and the discharge nozzles, because grease build-up on these devices can render th e system ineffective. 308

CHAPTER 19: Special Age nt Extinguish ing Systems

TABLE 19·3

Testing and Inspection Guidelines for Dry Chemical Systems

Verification or Test

Minimum Frequency

Owner Overall physica l ap pearance (owner)

Every 30 days

Access to act ivation devices Detector status Nozzles status Piping status Cylinder status Service/Maintenance

Organization

1. Initia l physical inspect ion

Every 6 month s

Access to activation devices Detector stat us Nozzles status Piping status Cylind er status Changes in th e hazard 2.

Examine all detectors, conta iners, releasing devices, piping, hose assemb lies, nozzles, alarms, and auxiliary equ ipment*

3. Verify the operation of the detection system 4.

Remove and clean discharge nozzles, verify discharge nozzles are not clogged

Every 6 months

Every 6 month s Every 6 months

5. Verify that agent d istribu t ion pip ing is not obstructed

Every 6 month s

6.

Every 6 months

Examine the agen t cylinders

7. Operational test of the system and all of it s functions

Every 6 months

(excluding discharge)

8. Replacement of the fusib le links

Every year

9. Hydro stati c test

Every 12 yea rs

Note: For all of these verifications and tests, t he actuat ing controls must be remo ved from the age nt containe rs to avoid accidental discharge. * Nozzle blow-off caps, where provided , shou ld be intact and und amaged . Nozzles should be correc t ly aimed. All detector s, containers, releasing devices, piping , hose assemb lies, nozzles, alarm s, and auxiliary equipme nt should be free from damage and in good work ing order. Nozzles that are located above / near equipment that may cause grease o r other deposits should be removed and cleaned o r replaced eve ry 6 months .

309

SECTION 2: Building Systems and Fire Protect ion Systems

TABLE 19·4

Testing and Inspection Guidelines for Wet Chemical Systems

Verification or Test

Minimum Frequency

Owner

Overall physical appearance (owner)

Every 30 days

Access to activat ion devices Detector status Nozzles status Piping status Cylinder status Service/Maintenance

Organization

1. Initial physical inspection

Every 6 months

Access to act ivation devices Detecto r statu s Nozzles status Piping status Cylinder status Changes in the hazard 2. Examine all detectors, conta iners, releasing devices, piping, hose assemblies, nozzles,alarms, and auxiliary equip ment*

Every 6 months

3. Verify the operation of the detect ion system

Every 6 month s

4. Remove and clean discharge nozzles, verify discharge nozzles are not clogged

Every 6 months

5. Verify that agent distributi on piping is not obstr ucted

Every 6 months

6. Examine the agent cylinders

Every 6 months

7. Operationa l test of the system and all of its funct ions (excluding di scharge)

Every 6 month s

8. Replacement of the fusible links

Every 6 months

9. Rep lace non-fusible temperatu re sensors

Everyyear

10. Hydrostatic test

Every 12 years

Note: For all of th ese verification s and tests, the actuati ng contro ls mu st be remove d from the agen t co ntain e rs to avo id acciden tal di scharge. *Nozzle blow-off caps, w here prov ided, shou ld be intact and und amaged . Nozzles should be co rrectly aimed. All det ector s, co ntainers, re leasing devices, pi ping, hose assemblies, nozzles, alarm s, and auxiliary equipment should be free from damage and in good wo rking order. Nozzles th at are located above/ near equipment that may cause g rease or ot her dep osits should be remo ved and cleaned o r rep laced every 6 mo nth s.

310

CHAPTER 19: Special Age nt Ext inguish ing System s

NFPA Codes, Standards , and Recommended Practices

See the latest version of the NFPA Catalog for availability of current editions of the following documents. NFPA NFPA NFPA NFPA NFPA

12, Standard on Carbon Dioxide Extinguishing Systems 12A, Standard on Halon 1301 Fire Extinguishing Systems 12B, Standard on Halon 1211 Fire Extinguishing Systems 17, Standard for Dry Chemical Extinguishing Systems 17A, Standard for Wet Chemical Extinguishing Systems

311

CHAPTER

20 CLEAN AGENT EXTINGUISHING SYSTEMS Tom Wysocki

Gaseous fire extinguishing agents, which are clean, dry, electrically nonconductive, and "life safe" at normal extinguishing concentrations , are classed as "clean agents:' Genera lly, clean agent systems are intended to protect the contents of a space and permit quick resumpti on of normal operation of a facility even after a fire and a discharge. The use of clean agents is covered by NFPA 2001, Standard on Clean Agent Fire Extin guishing Systems .

TYPICAL APPLICATIONS Clean agents are typically used totally to flood spaces that m ay be occ upied by per sonne l where a clean, dr y, electrically n onc onducti ve agent is req uired. A common appli cation of clean agents is th e protection of electronic equipment found in data pro20-1). Other cessing centers, telecommunications facilities, and control roo ms (FIGURE app lications include large, pot entially occ upied spaces where flammable liquid s are the fire haz ard . When such a haz ard requires rapid fire suppression, but th e evac uation of personnel prior to disch arge of the extinguishing system may not be possible, a clean agent system ma y be suitable for us e. Flammable liquid s storage and mixing rooms in large indu strial facilities and pump roo ms in petrochemica l facilities are examp les of this latter application . "Loca l applic ation" clean agent system s are found protecting ma chin ery, such as computer num erical cont ro l (CNC) machines, where flamm able liquids proc essing and handlin g are the potential fir e hazard .

CLASSESOF CLEAN AGENTS To meet th e definition of a clean agent p er NFPA 2001, an agent must be an electric ally noncon du ctin g, vo latile or gaseo us fire extin gu ishing agent th at does not leave residue up on evap oration. Two genera l categori es of clean agent s are recog niz ed :

CHAPTER 20: Clean Agent Extinguishing System s

l.

2.

Halocarbon agents whose primary components include one or m ore organ ic compounds that contain one or more of the elements fluorine, ch lorine, bromine, or iodine . Ha locarbons include hydrofluorocarbons, hydrochlorofluorocarbons, perfluorocarbons, fluoroi o docarbons, and fluoroketones. In ert gas agents whose primary compon ents are one or more of the gases heli um, argon, nitrogen, or neon. Inert gases may contain a sing le gas or a mixture of the aforeme n tioned gases. Blends of these gases may also conta in carbo n dioxide as a seco nd ary component.

Use Considerations Given sufficient agent concentrat ion, clean agents may be us ed to extinguish fire in a variety of liquid, gaseous, and solid fuels. The use of clean agents on Class A fuels and

(!) Storage container(s) @Automatic

fire detectors

@ Discharge nozzles installed in room @ Discharge nozzles installed in subfloor area @Manual

release device

@Aud ible and visual predischarge alarm device

® Control panel @ Air sampling detection unit (for cabinets) FIGURE 20-1 Typical c lean age nt system installed in a room wit h a subfl oo r area.

313

SECTION 2: Bui ld ing Systems and Fire Protec t ion Systems

solid mat eri als generally should be limit ed to extingui shm ent of shallow surfa ce burn ing. Clean agents are n ot effective for fires involving ch emical s th at contain thei r own oxygen supply (such as cellulose nitrate) , reactiv e m etals (su ch as so dium, potassium, ma gnesium, titanium , zirc onium ), or th e m etal hydrid es. Fires in solid m aterial s that extend und er th e surfac e of th e m ateri al, comm only kn own as "deep sea ted " fires, pr esent a p arti cular challenge . Th ese fires are usually extingu ished by reducing the fuel temperature, either directl y by applicati on of a heat absorbing m edium , such as water, or by blanketing with an in ert gas. The in ert gas slows th e reacti on rate to th e p oint whe re heat gen erated by oxidation is less th an heat losse s to sur ro undin gs. This cau ses the temp eratur e to fall below th e level necessary for sp ontane ous igniti on after rem oval of th e in ert atm osph ere. The requir ed con centrati on for use of an in ert gas to extingui sh "de ep sea ted" fires in solid s mu st be determin ed by an applic ation-sp ecific test.

SAFETYCONSIDERATIONS General On e of the prima ry advant ages of clean agents over oth er gaseo us agent s such as carbon dioxid e is the ability of th e clean agent to extingui sh m any fires at con cent rations th at will supp ort hum an life. Noneth eless, th ere are p otential ha zard s asso ciat ed with th e discharge of a clean agent system. The clean agent s are discharged at relatively high pr essur e from nozzles design ed to distribut e an d mi x th e clean agent with th e atm osph ere ins ide a pro tected area. The potenti al hazar ds caused by th e high-velocity je t includ e: 1. 2.

Noise th at can be startlin g but ordin arily in sufficient to cause injury. Turbu len ce th at m ay be sufficient to dislodge sub stanti al objects dir ectly in the agent discharge path . En ough genera l tu rbulence in th e pro tecte d area to m ove un sec ur ed pape r and light objects is typica l.

Cold Temperature Any cont act with vapo ri zing haloca rb on liquid discharge should be avoided. As the liquid vap orizes, th e tem pera tur e decreases rapidly and can cause frostbite burn s to the skin . Because th e liquid vap ori zes r apidl y in air, th e hazar d is limi ted to th e area n ear th e point of disch arge. The rap id decrease in temp era tur e m ay pro du ce a light fog as the water vapo r in th e air cond enses, resu ltin g in a red uction of visibili ty. The limit s for expos ur e (inh alation) of atm osp heres floode d with clean agent s are given in NFP A 200 1. For halocar bon clean agents used be low their No Observed Ad verse Effect Limi t (N OAEL), maximum expos ure tim e is spec ified to b e no longer than 5 minut es. At con cent rat ions above th e NOAEL, m or e strin gent limit ations rela ted to personn el expos ure are specifie d by NFPA 200 1 an d th e U.S. Enviro n men tal Pro tect ion Agency. 314

CHAPTER 20: Clean Agent Ext ingu ishing Syst em s

For in ert gases used at concentrations up to 43 percent (12 percent sea- level eq uivalent oxygen concentration), exposure of personnel to the reduced oxygen concentration should be no longer than 5 minutes. For more detail on exposure limitations, see NFPA 2001. Unnecessary exposure to atmospheres flooded by clean agents should be avoided; therefore, when possible, personnel should evacuate the protected space prior to the discharge of a clean agent system . Personnel who regularly en ter spaces protected by clean agent systems shou ld be trained to follow the correct response procedures to system alarms and warnings, proper evacuation procedures, system operati ng procedures, and the health and safety considerations associated with agent discharge. Visitors who on ly occas ionally enter protected spaces for brief periods of time shou ld be accompanied by personnel who are familiar with the system and related safety considerations and will be respons ibl e for directing a visitor's response in case of a system alarm or discharge. If the visitor may not be continuously accompanied by a responsible person, the visitor needs to be trained in the safety aspects related to the clean agent system.

SERVICING The equipment incorporated in clean agent systems is highl y spec ialized. The agent is stored in high-pressure containers . Pressures within the containers may be as high as 4500 psi (310 bar) und er normal conditions. Such pressures are far in excess of the pressures encountered in fire sprinkler systems as well as most types of water-b ased fire protection systems; thus, qualification as a sprinkler fitter or fire sprinkler service professional is not sufficient to service a clean agent system safely. Further, the agent storage container valve and other release devices are designed to open rapidly and quickly discharge the agent - for halocarbon agents, the contents of th e container will discharge in 10 seconds or less. These conta in ers, if not prop erly secured and hand led, can become projectiles capable of severe ly injurin g or killing people and destroying propert y (FIGURE 20-2). Personnel with proper training and equipment to service th e spe cific make and model of clean agen t system are th e on ly ones who shou ld be tasked with these duties .

IN CASE OF FIRE Mo st clean agent systems are equipped with predi scharge time delays and alarms. When th ese alarms sound, personnel should evac uate th e space to avoid the hazards associated with fire in the protected space and to avoid expos ure to p ossible hazards assoc iated with th e agent discharge.

AFTER FIRE After a dischar ge, the ha zar d should be inspected by speci ally tra ined perso nnel equipp ed with self-contained breathing apparat us. Once it is determ in ed th at the fire

315

SECTION 2: Build ing Syst ems and Fire Protect io n Systems

FIGURE 20-2 This clean agent co nt ainer was not prop erly secured w hen an unq ualified individual accidentl y o pened t he cylinder valve. The discharging cylinde r propel led it self thr ough th e ceiling and roo f of the bu ilding and came to rest on the roof as show n in th is pict ure. Fortunat ely, there we re no inj uries to personnel.

has been extinguish ed and the hazard secured again st reflash, th e space should be purg ed of products of combusti on and clean agent. The meth od of purgin g th e atm ospher e will depend on local conditi ons. Provision should b e made to have th e system servic ed and re charged by qualifi ed p ersonn el. If th e prot ec ted sp ace mu st be return ed to operati on pri or to restorati on of th e clean agent syst em to full operat ing condition , provisions for altern ate fire prot ecti on accept abl e to the facility owner and th e auth oriti es h aving juri sdicti on should be enact ed.

INFORMAL AND FORMAL INSPECTIONS A clean agent fire system is a combin ation of fire extin gui shin g agent and electric al and m ech ani cal devices th at mu st be regul arly inspe cted and m aint ained to ke ep the system in good op era tin g conditi on. Form al inspecti ons must be p erform ed by specially train ed qualifi ed p erso nn el, workin g in conjun ction with th e fire inspector, at interv als specified by code or regulation. NFPA 2001 pro vides details on th e frequenc y and natur e of requir ed insp ecti ons (TABLE 20-1). NFPA 72®, Na tional Fire A lar m and Signaling Code, should also be consulted for inspection and test requir ement s relat ed to th e elect ronic detec tion and cont ro l unit s th at form a part of th e clean agent extin guishing system . Betwe en form al inspe ction s and m aint enan ce, personn el mu st be alert for obvio us conditi ons th at could imp air th e proper operati on of th e system in case of fire. As part of the tr ainin g of p ersonnel in th e op er ation of th e system , personn el should be instru cted to be alert for obvious conditi ons th at co uld imp air op eration of th e system or indi cate th at the system m ay need m aint enan ce. Access to m anu al stations mu st rem ain un obstru cted. Objects includin g equipm ent and partiti ons mu st n ot be place d close to any sys tem n ozzle, wh ere the objects could possibly obstru ct or divert th e flow 316

CHAPTER 20: Clean Agent Extinguishing Systems

TABLE 20-1

Inspection and Testing Guidelines for Clean Agent Systems

Verification or Test 1.

Re-evaluate the system and make any required mod ification s to the syst em to retain th e intended performance of th e system.

Frequency (See note A) Anytime cha nges are made to the hazard enclo sure, configuration of equipment or partitions wit hin th e hazard, or fue ls contained w ithin the hazard, it is the facil ity owner 's/o perator's responsib ility to arrange fo r reevaluation of the system by competent personn el.

2. Thoroughly inspect general condition of the system.

Month ly

3.

Check agen t quantit y and co nt ainer pressure (See note b.)

Semiannually

4.

Inspect enclosure/hazard, check for change s to bot h.

Annua lly

5. Test supervised circuits. 6.

Test control panel.

7. Test power suppl y including standby batt eries. (See not e c.)

Annua lly Annua lly Annua lly

8.

Inspect, clean, and test detecto rs.

Annua lly

9.

Test time delay (if appli cable).

Annua lly

10. Test alarms.

Ann ually

11. Test auxi liary functio ns, such as venti lation co ntrol s, d oo r closers; verify fu nct ionalit y of equipment shutd owns.

Annua lly

12. Test manual and automatic release devices.

Annua lly

13. Inspect system componen t s, includi ng pip ing, nozzles, and support s.

A nnuall y

14. Inspect system ho se(s).

An nually

15. Test system hose(s).

Every 5 yrs

16. Com p lete external inspect ion of co ntai ners.

Every 5 yrs in accordance w ith Section 3 of CGA C-6, excep t that the cy lind ers need not be empt ied and shall not be stamped w hile und er pre ssure.

17. Perfor m hydrost atic testing of inert gas age nt co ntain ers; perform hydro static test or comp lete visual inspection of liquefied comp ressed gas agent co ntainers.

After a d ischarge, if mo re th an 5 yrs since last test or co mpl ete inspect io n.

a) Frequ ency is t he minimum recommen ded. b) For items 3 throug h 17, t he actuat ing con t rols must be removed from the co ntaine r fo llowi ng man ufact urer's instr uctio ns to p revent accidenta l discha rge. c) Where engine-dri ven ge nerato rs provide po wer, more freq uent test ing in accorda nce w it h NFPA 110 is requi red.

3 17

SECTION 2: Building Syst ems and Fire Protect io n Systems

from the nozzle. Tamper seals should be in place on all manual controls for the system (FIGURE 20·3). If the fire system control panel is located in an area frequented by personnel, they should be taught to recognize tro uble alarms at the control panel. These are examples of conditions that can be recognized by ope rating personnel and brought to the attenti on of m anagement for immediate corr ective action. Personnel should be instructed never to bl ock doors or other openings in th e enclosur e- in case of a discharge, the clean agent will escape through the opening in the enclosure and possibly pr event th e system from developing th e proper fire extinguishing concentration in the protected space. If it is n ecessary to be able to keep doors ope n for peri ods of time in or der to m ove supplie s or equipm ent in and out of th e protected space, doors sh ou ld b e equipp ed with automatic door h older s interl ocked to r elease th e d oo rs up on activa tion of the clean agent system-personnel should be in stru cted to use the au toma tic door h old ers and ne ver block doors ope n. A visual inspection of th e sys tem at periodic intervals, weekly or monthly depending on loca l conditions, should be m ade by personnel who are train ed to recognize obv ious imp airm en ts. Items th at sh ou ld be checked during this periodic wa lk-throu gh includ e: l.

2.

3.

4. 5. 3 18

(a)

(b)

System con tro l panel power inFIGURE 20-3Tampe r seals help ret ain safety pins dicator n orma l. in place and serve to ind icate if t he safety pin No abnormal (trouble or had been removed after the last inspecti o n. A missing tamper seal sho uld be repo rted to alarm) condit ions indicated on manage ment, and a reinspect io n of t he system system contro l pane l. sho uld be done at once . Nozzles and pipe are intact and sh ow no signs of damage. Tamper sea ls in place on all manual release devices. Cylind ers sh ow n o sign of physical damage .

CHAPTER 20: Clean Agent Ext ingu ishing Syst em s

6. 7. 8.

Cylind er gauges in normal (green) range. Overall physical condition of system appea rs good. No changes to the protected area.

If changes are made to the protected area b etween regularly schedu led inspections, the owner/operator of the facility shou ld engage th e services of a fire protecti on professiona l well versed in clean agent systems to reevaluate the system's adeq uacy in light of the change, such as a reconfigurat ion of the space, or a change to the type of hazard being pro tected. Some changes that warrant a reeva luation of the system include: 1.

2. 3. 4. 5. 6.

New openings in the enclosure boundary, walls, floors, ceilings. Relocati on or addition of part itions within the protected space. Additi on of equ ipment or other objects withi n the protected space that might block the free flow of agent from the system nozzles. Expansion of the protected space. Reduction in size of the protected space . Cha nge in th e type of equipment or fuels pr esent in the protected space.

REQUIRED FORMAL INSPECTION AND MAINTENANCE The requ irement that th ose who inspe ct and maintain clean agent system equipment be prop erly qualified to work on the specific mak e and model of equipm ent cannot be overemphasized. A comp lete set of as-bui lt system insta llation drawings shou ld be availabl e to the inspector along with the system manufactur er's installati on and maintenanc e m anua ls. The inspector should also have access to and have studied all service bu lletins issued by th e system manufacturer for th e insta lled equipment. The inspector should use a checklist developed for the spec ific system install ation. The Bibliography of thi s chapter contains references to publications that are helpful in developing appropriate checklists . Attempts by unqualified persons to perform insp ect ion, tests, serv ice, and m aint enance of these systems are a cause of unwanted system discharges. Business interruption, cost of recharge, and unn ecessary hazard to personne l are som e of the undesirabl e results of unwant ed discharges. If cylinder reinspection is to be done (see the Five- Year Tests section later in this chapt er), the insp ector shou ld be familiar wit h th e guid elin es related to cylinder inspection an d test criteria in NFPA 200 1, the Compressed Gas Associatio n (CGA) rul es, and with app licable governmenta l regulations .

PERSONAL SAFETYDURING INSPECTIONS Inspectors should wear appropriate personal protection eq uipm ent. Depending on loca l conditions and the type of inspection work required, personal protective equ ip ment m ay include safety glasses, hard hat , safety shoes, and hearin g protection. Hearing 319

SECTION 2: Building System s and Fire Prot ect io n System s

protection should be worn if inspectors are to remain in the vicinity of alarm devices during their testing. Wh ereas most clean agent systems are equipped with predischarge warnings, some systems are not; also, failures of th e predis charg e warnings are possibl e. Inspectors should be aware of the possibility of a discharge from a nozzle at any time. In particular, inspectors should never put themselves in the path of th e discharge from a nozzle . It is generally desirable to perform inspections when the facility is not in operation, with only personnel involv ed in supervising or performing the inspection present. In many facilities protected by clean agen t systems, however, it is n ot possible to schedule inspections during downtime. Facilities requiring clean agent protection are often in operation "24/7" 365 days per year. Personnel in and around the protected area should be informed of the inspecti on, provided with hearing pr otecti on if they must be in the area where alarms will sound, and instructed as to the procedures to be followed during the testing. They likewise should be instructed as to proc edures should a fire occur while the system is being tested . If eq uipment is interl ocked with the system controls, permission to activate the interl ocks and shut down (or start) the interlocked equipm ent should b e sought from the facility manag ement. If actual equipm ent shutdown is not permitted , prov ision should be made to test the interlocks with the actual control of equipment bypassed.

SEMIANNUAL INSPECTION The pressure in agent storage containers and th e qu antity of agent in th e containers must be checked at least onc e every 6 months. The quantity of hal ocarbon agent in th e container may be determined by weighing the container or by use of approved liquid level-i ndicating devices. If a liquid level- indicating device is used, it is essenti al th at the device be approved for use with the particular mak e, model, and size of agent storage cont ain er. Compensation for am bient storage temperature mu st be taken int o account when using liquid level indicat ors. The quantity of n onliquefi ed inert gas in a cont ain er is directly related to th e pressure corrected for temperat ure in the contain er; th erefore, determination of the quantity of iner t gas is m ade by accu rately m easurin g th e pressure in the container and correcting the pressure for temperature . Ha locarbo n containers showi ng a loss of agent quantity exceedin g 5 pe rcen t or a loss of pressure exceed ing 10 percent (corrected for temp era tur e) mu st b e reinspected and tested accor din g to app licab le government regu lations and then refilled . Nonliquefied inert gas agent con tain ers showing a loss in pressure exceed in g 5 pe rcent corrected for temp erat ur e mu st be reinspected and tested accordin g to applicable governm ent regulations and then refilled. Any obvious signs of damage to a cylind er or signs th at th e cylinder was heated to extr em e temperature (overheated) m ake it ne cessary for th e cylind er to be emptied an d either condemned or requalified. Note that halocarbon agents must be collected and eith er recycled or disposed of in an environme nt ally sound manner in accordance with applicable laws and governmen tal regulations [see 49 Code of Federa l Regulat ions (CFR) 180.205 (d), Pipeline and Hazar dous Materials Safety Administration, Depart ment of Transportation, United States Government] . 320

CHAPTER 20: Clean Agent Ext ingu ishing Syst em s

ANNUAL INSPECTION A comp lete forma l inspection, test, and maintenance of the overall system is required at least once a year. The yearly inspection includes a thorough check of the enclosu re for penetrations or other changes that adversely affect the ability of the system to develop and maintain the design concentrat ion. If there is question as to the integrity of the encl osure, it may be nec essary to perform a door fan test and compa re the results with those obtained during the system's commiss ioning. It also incl udes an inspection of the distribution system, wh ich is the hoses, pipe, and nozzles, for physica l damage and corros ion. Nozzle orifices should be clean and free of obstructions. Hoses must be tested or replaced if the visual inspecti on indicates any deficiency. Other components of the distribution system mu st be repaired or rep laced if the inspecti on indicates any deficienc y. Tests of detection and control equipment, release devices, and anc illary equipment should also be performed at least ann ually. Thes e tests inclu de th e testing of the initiating circuits, control pa n el, power supp ly, automatic detectors , tim e delays, alarms, ventilation controls, door closers , eq uipment interlocks, and release devices (automa tic and manual). If th e enclos ur e is eq uipped with pressure relief vents to vent pressure build -up during a discharge, these vents shou ld be cycled and checked for correct operation. If abort switches are provided , they should also be tested. To prevent accidenta l release of clean agent, it is essentia l that the system discharge be disab led during testing of detection and contro l equipment. Particular attention should be given to a system's automatic detection and controls in order to elimi nate false alarms . A false alarm from th e detec tion and contro l system of a clean agent system can be particularly serious. Whereas a false alarm from a fire alarm system is a nuisance and is undesirab le, false alarms from the fire alarm contro ls of a clean agent system can cause eq uipm ent shutdowns and disc harge of clean agent. After th e inspection, deficienci es must be corrected and the system returned to full opera ting status. A report on the in spec tion and correc tive actions taken should be filed with the owner and appropr iate aut h orit ies.

FIVE-YEARTESTS Every 5 years, all system h oses must be tested at 1½ tim es the maximum container pressure at 130°F (54.4°C) or rep laced. A comp lete externa l inspection of the containers, in accordance with Section 3 of CGA -6, Standard for Visua l Insp ection of Steel Comp ressed Gas Cylinders, is required by NFPA 200 1 every 5 years. This inspection includ es checking the cylind er for corrosion, physical damage, and distortion or any other defect that may indi cate the cylind er is unfit for service. The externa l in spection do es not requ ire containers to be empt ied, and it is forbidd en to stamp conta iners that are und er pres sur e. Rather than stamp ing the cylind er, an inspection tag on th e cylind er must be comp leted by th e inspe ctor . And , finally, if a conta in er needs to be rechar ged because of leakage or because it was discharged, th ere are governm ental requirement s for reinspection and testing of the cylinder s th at mu st be followed . The requirements vary by country and also by th e typ e of cylind er and type of agent. 32 1

SECTION 2: Build ing Systems and Fire Protect ion Systems

BIBLIOGRAPHY CGA-6, Standard for Visual Inspection of Steel Compressed Gas Cylinders, Compressed Gas Association, Arlington, VA, 1993. Fire Protection System Inspection Guidelines, Fire Suppression Systems Association, Baltimore, MD, 2010. NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Cata log for availability of current editions of the following documents. NFPA 72®, National Fire Alarm and Signaling Code NFPA 200 1, Standard on Clean Agent Fire Extinguishing Systems

322

CHAPTER

21 \.

PORTABLEFIRE EXTINGUISHERS Mark Conroy

Portab le fire extin guis hers are installed in occupa nci es to give th e building occupa nt s a means of fighting a fire manua lly. Not all occupa ncie s are req uired to have portable fire extingui shers. Usually, a building code , an occupa ncy standard, a fire code (NFPA l, Fire Code) NFPA 101®, Life Safety Code®, or an insurance compa ny req uir eme nt will have a provision that stat es somet hin g sim ilar to, "Por table fire ext ingui shers shall be installed in accor dance with NFPA 10, Standard for Portable Fire Extinguishers:' Onc e it has been estab lish ed that portab le fire extinguishers are req uir ed, the inspector must ens ure th at th ey are properly selected, placed, and serviced. In ad diti on , the in spec tor should verify th at a training program is present if occupants are expec ted to use portab le extingui sh ers. It is recommended that this tr aining program in corpora te th e "fight -or- flight" approac h to usin g a fire extinguisher. A good reference for suc h a program is a video produced by the National Fir e Protection Association (NFPA) entitled Fire Extinguishers: Fight or Flight. The int enti on of th e fight -orflight approac h is simply to size up a fire and determine whether it is safe to fight with an extingui sher. Also included in this approach is guidance, such as never fight a fire in a smoke -filled space, always fight th e fire with your back to the escape rou te, and always make sure that someone is ca lling th e fire depar tment before attemptin g to fight th e fire with an extinguis her. All of th is information, and more, is contain ed wit hin this video .

SELECTING EXTINGUISHERS NFPA 10 defines five categor ies of fires, which are used to help with th e select ion of the correct portable fire exting uisher for the expected condit ions. The categories are : 1.

2.

Class A Fires. Fires in ord in ary combus tibl e materia ls, such as wood, cloth, paper, rubber, and many plastics. Class B Fires . Fires in flammab le liquid s, combustib le liquid s, petroleum greases, tars, oils, oil-based pa ints, solven ts, lacq uers, alcoh ols, and flamm able gases .

SECTION 2: Bui ld ing Systems and Fire Protec ti on Systems

3. 4. 5.

Class C Fires. Fires that inv olve energized electrica l equipment. Class D Fires. Fires in combustible metals, such as magnesium, titanium, zirconium, sodium, lithium , and potassium. Class K Fires. Fires in cooking app liances that involve combustible cooking media (vegetable or animal oils and fats).

The size and type of portable fire ext inguisher is based on the amount of Class A combustible materials, th e amount of Class B flammables, or, for some occupancies, a combination of both. For many areas, the extinguishing agent must also be compatible with ene rgized electrical equ ipm ent. NFPA 10 provides the following criteria for determining the classification of hazards.

Light (Low) Hazard Light (low) hazard occupancies are classified as locations where the quantity and combustibility of Class A combustibles and Class B flammables are low, and fires with relatively low rates of heat release are expected. These occupa nci es consist of fire hazards having typica lly expected quantities of Class A combustib le furnishings. Also, where flammable liquids are present, the total anticipated quantity of these liquids must be less than 1 gal (3.8 L) in any room or area. These occupancies may include buildings or rooms occupied as offices, classrooms, churches, assembly halls, and guest room areas of hotels. This classification anticipates that the majority of content items is either noncombustible or so arranged that a fire is not likely to spread rapid ly. Small amounts of Class B flammables, such as those used for duplicating machines and art supplies, are permitted, provided that they are kept in closed containers and safely stored.

Ordinary (Moderate) Hazard Ordinary (moderate) hazard occupancies are classified as locations where the quantity and combustibility of Class A combustib le materials and Class B flammables are moderate, and fires with moderate rates of heat release are expected . These occupancies consist of fire hazards that only occasionally contain Class A combustible materials beyond normal an ticipated furnishings . Where flammable liquids are present , the total anticipated quantity of these liquids must be from 1 to 5 gal (3.8 to 18.9 L) in any room or area . These occupancies may consist of dining areas, mercantile shops and allied storage, light manufacturing, research operations, automob ile showrooms , parking garages, workshop or support service areas of light hazard occupancies, and warehouses containing Class I or Class II commodities as defined by NFPA 13, Standard f or the Installation of Sprinkler Systems .

Extra (High) Hazard Extra (high) hazard occupancies are classified as location s where the quantity and com bustibility of Class A combustible materials are high or where high amounts of Class B flammable s are pre sent, and rapidly deve loping fires with high rat es of heat release are expected. Thes e occupanci es consi st of fire hazards involv ed with the storage, 324

CHAPTER 21: Portable Fire Extinguishers

packaging, handling, or manufacture of Class A combustib les. Where flammable liq uids are present, the total anticipated quantity of th ese liquids is expected to exceed 5 gal (18.9 L) in any room or area . These occupancies may consist of woodworking, vehicl e repair, aircraft and boat servicing, cooking areas, individual product display showrooms, product convention center displays, and storage and manufacturing processes, such as painting, dipping, and coating, includin g flammable liquid handling. Also includ ed is ware housing of or in -process storage of other than Class I and Class II commodities.

DISTRIBUTING EXTINGUISHERS After the hazard classification of an occupancy has been determined , the portable extinguishers can be distributed. Exti nguis hers should be placed in loca tions that are readily available, provide easy access, are relatively free from temporary blockage, are near usual paths of travel, are near exits and entrances, and are free from the potential of physical damage.

Mounting Extinguishers Most ext inguishers are mounted on wa lls or columns by secure ly fastened hang ers so that th ey are supported adequately, although so me extinguishers are mounted in cabinets or wa ll recesses . In any case, the operating instructions must face outward, and the extinguisher shou ld be pla ced so that it can be removed easily. Cabinets shou ld be kept clean and dry. In areas where extinguishers may bec ome dislodged, brackets specifically design ed to cope with this prob lem shou ld be used. In areas such as warehouse aisles, where they are subject to physical damage, they should be protected from impact. In large open areas such as aircraft hangars , extinguishers can be mounted on mo vab le pedesta ls or wheeled car ts whose proper loca tions should be marked on the floor to maintain th e pattern of distr ibution. NFPA 10 specifies floor clearance and mounting heights bas ed on extinguish er weight. Extingu ishers with a gross weight of no m ore than 40 lb (18.14 kg) should be installed so that the top of the extinguisher is n ot more than 5 ft ( 1.5 m) above the floor. Extinguishers with a gros s weight greater than 40 lb (18.14 kg) (except whee led types) should be installed so th at th e top of th e exti nguisher is n ot more than 3.5 ft (1.07 m) above the floor. In no case should the clearance between the bottom of the extinguisher and th e floor be less than 4 in. (10.2 cm) . When extinguishers are m ount ed on industrial trucks, vehicles, boats , aircraft, trains, and other transportation mod es, specia l mounting brackets, available from the manufactur er, shou ld be used. It is important to inst all an extinguisher at a safe dist ance from a hazard so that access to the extinguish er does not become blocked by a fire.

Distribution for Class A Hazards The NFPA 10 requirements for determinin g the minimum number and rating of extinguishers ne eded in any particular area to cope with Class A fires are provided in 325

SECTION 2: Build ing Systems and Fire Protect ion Systems

TABLE 21-1. Sometimes, extin guishers wit h ratings higher tha n those ind icated in th is table will be necessary because of process hazards or building configu ration. In no case, however, should there be fewer than the minimum calcu lated quantity of extinguishers, nor shou ld the maximum travel distance be exceeded. The first step in calcu latin g how many Class A extingu ishers are needed is to determine whether an occupancy is a light, an ordinary, or an extra hazard occupancy. Next, th e extinguisher rating shou ld be matched with the occupancy hazard to determine the maximum area an extingu isher can protect. The maximum travel distance, or actual walking distance, allowed is also specified in Table 21 - l. For Class A extinguishers, it is 75 ft (23 m). Thus, a 2.5-ga l (9.5-L) stored-pressure water extinguisher rated 2-A will protect an area of 6000 ft2 (558 m 2) in a light h azard occupancy bu t onl y 3000 ft 2

(279 m2) in an ordinary hazard occupancy. TABLE 21-2was deve loped from Table 21 - 1 and summarizes what was in tended by the first three rows of Table 21- 1. The followin g examples show how to place extin guis hers in accordance with these tables, both of which were taken from NFPA 10. Example 1. Determine the minimum number of extinguishers required for Class A fires according to maximum floo r area per extinguisher listed in Table 21 - 1 given a building area of 67,500 ft2 (6271 m2). The dimensions of the outside walls of the building are 450 x 150 ft (137 x 46 m). The maximum floor area per extinguisher for all occupancies is 11,250 ft2 (1045 m2), according to Table 21 - 1.

TABLE 21·1

Fire Extinguisher Size and Placement for Class A Hazards

Light (Low) Hazard Occupancy

Ordinary (Moderate) Hazard Occupancy

Extra (High) Hazard Occupancy

2-At

2-At

4-A*

Maximum floor area per un it of A

3000 ft 2

1500 ft 2

1000 ft 2

Maximum flo or area fo r exting uisher

11.250 ft2**

11.250 ft 2**

11.250 ft 2**

Maximum travel d istanc e to extinguishe r

75 ft

75 ft

75 ft

Minimum rated sing le extingui sher

For SI unit s: 1 ft = 0.305 m; 1 ft 2 = 0.0929 m2

"Two 2½-gal (9.46- L) w ater-ty pe extin g uishers can be used to fulfil l th e req uirement s of o ne 4-A rated extin g uisher. **See E-3.3. t up to two water-ty pe extingui shers, each w ith l ·A rat ing, can be used to fu lfill th e requir ement s of o ne 2-A rated ext ing uisher.

326

CHAPTER 21: Portab le Fire Exti ng u ishers

TABLE 21·2

Maximum Area to Be Protected per Extinguisher (ft2)*

Class A Rating Shown on Extinguisher

Light (Low) Hazard Occupancy

Ordinary (Moderate) Hazard Occupancy

Extra (High) Hazard Occupancy

lA 2A

6000

3000

3A

9000

450 0

4A

11,250

600 0

6A

11,250

9000

600 0

l0 A

11,250

11,250

10,000

20A

11,250

11,250

11,250

30A

11,250

11,250

11,250

40A

11,250

11,250

11,250

4000

Fo r SI u nit: 1 ft 2 = 0 .0929 m 2 Not e: 11,250 ft 2 is co nside red a pract ical li m it.

A floor area of 11,250 ft 2 (1045 m 2) per extinguish er requires the extinguis hers to have a Class A rating of at least 4-A for a light hazard occ upanc y, 10-A for an ordinary hazard occupancy, or 20-A for an extra hazard occupa nc y, according to Table 2 1-2. For this examp le, n ote that in sta llin g extinguish ers with hi gher Class A rat in gs wi ll not affect distribution or placeme nt, because of the guideline s in Table 21 -2 on the maximum area to b e protected per extinguish er. 67,500 ft2Jl 1,250 ft2 = 6. Six extingui shers rated 4-A for light hazard occupa n cy. Six exting uisher s rated 10-A for ordinary hazard occ up ancy. Six extinguish ers rated 20-A for extra hazard occ up ancy. Placement of the exting uishers along the outs id e wa lls in thi s examp le wou ld not 21·1). be acceptab le because the maximum travel distance wou ld be exceed ed (FIGURE Additional extinguishers are needed , or new calculations need to be cond ucted using extingui shers of lower ratings. Example 2. Using the building designated in Example l , determine the minimum number of extinguis h ers required for Class A fires when a floor area per extingui sher of 6000 ft2 (557 m 2) is used. A floor area of 6000 ft2 (557 m 2) per ext inguis her requires the extingu isher s to hav e a Class A rating of at least 2-A for a light hazard occupancy, 4-A for an ordinary hazard occupancy, or 6-A for an extra hazard occ upan cy, accord ing to Table 2 1-2. 327

SECTION 2: Building Systemsand Fire Protection Systems

450 ft (137.2 m)

FIGURE 21·1 Diagrammatic represe ntat ion of extinguishers located along outside walls of a 45O-ft x

15O-ft(137-m x 46-m) building. [The dots represent extingu ishers. The shaded areas indicate"voids" that are farther than 75 ft (227 m) to the nearest extingu ishe r.] Source: NFPA 10,2010,Figure E-3.6. 67,500 ft2/6OOOft2

= 12

12 ext in guishers rated 2-A for light hazard occupancy. 12 extinguishers

rated 4-A for ordinary hazard occupancy.

12 ext in guishers rat ed 6-A for ex tra hazard occupancy. Extinguishers could be mounted on exterior walls or on building co lumn s or interi21·2, and conform to both distribution and tra ve l distance or walls, as shown in FIGURE rules . NFPA 10 also allows up to half the complement of extinguishers for Class A fires to be replaced by uniformly spaced small hos e [l. 5-in. (3.81 -cm)] stations . H owever, the h ose stations and the extinguishers should be locat ed so that the h ose stations do not replace m ore than one of every two ext in guishers previously used.

Distribution for Class B Hazards In areas in which flammable liquids are n ot expected to reach an appreciable depth , extinguishers shou ld b e provid ed according to TABLE21-3, which was taken from N FPA 10. Th e basic maximum travel distanc e to C lass B ex tin guishers is 30 or 50 ft (9 .15 or 15.25 m) as opposed to 75 feet (23 m) for Class A extinguishers because flammabl e liquid s fir es r eac h th eir m aximum int ensit y alm os t imm ed iat ely, and thu s

FIGURE 21·2 Configuration rep rese nting 12 fire ext inguishers mounted on building columns or interior walls, in which requirements for both travel distance and fire exting uisher distribution are met . Source: NFPA 10,2010, FigureE-3.8.

328

CHAPTER 21: Portable Fire Extinguishers

TABLE 21-3

Fire Extinguisher Size and Placement for Class B Hazards

Type of Hazard

Basic Minimum Extinguisher Rating

Maximum Travel Distance to Extinguishers (ft)

(m)

30

9.14

Light (low)

5-B 10-B

50

15.25

Ord inary (moderate)

10-B

30

9.14

20-B

50

15.25

Extra (high )

40-B

30

9.14

80-B

50

15.25

Notes : (1) The specified ratings do not impl y th at fires of th e magnitudes ind icated by these ratings w ill occ ur, but rath er th ey are prov ided to give the operators mo re t ime and agent to hand le difficult spill fires that have the pote ntia l to occ u r. (2) For fires invo lving wate r-solubl e flamma ble liq uids, see 5.5.3. (3) For specific hazard applica tions, see Sectio n S.S.

th e extinguisher mu st be used earlier . Lower rated extinguish ers comp lying with the 30-ft (9.15-m) travel distance are typically installed unl ess an exti ngu isher with a SO-ft (15.25-m) trav el distance can be installed to protect more than one hazard . Where two hazards are no more than 60 ft (18.3 m) apart , one extingui sh er select ed from Table 21-3 with a 30-ft (9.15-m) travel distanc e can be placed between the two hazards , as long as the 30-ft (9.15-m) tra vel distance is n ot exceeded. Where two hazards are m ore th an 60 ft (18.3 m) apart, but not m ore than 100 ft (30.5 m) apart, one extin guisher selected from Table 21 ·3 with a SO-ft (15.25-m) trav el distance can be placed between the two hazards as long as the 50-ft (15.25-m) travel dist ance is not exceed ed. Wher e two ha zards are more th an 100 ft (30.5 m) apart, each hazard is pro vided with an extinguisher with a travel distanc e of 30 ft (9.15 m) based on Table 2 1-3. Wher e flammabl e liquid s are likely to reach an appreciab le depth, a Class B rated fire extin guisher must be provid ed on th e basis of at leas t two num erica l unit s of Class B extin guishin g potential per square foot (0.0929 m2) of flammable liquid sur face of the largest tank hazard in the area . Extingui shers selected to prot ect coo king appli anc es in which combu stibl e cooking media (vegetabl e or anima l oils and fats) is pr esent must be listed for Class K fires. Ext in guis hers list ed for Class K fire s are int end ed to be used in conjunction with an aut omati c fire protecti on system. A pla card must be install ed that states that th e fire prot ec tion system must be activ ated pri or to usin g th e fire ex tin guisher. The maximum trav el distanc e fr om th e exting uisher to th e ha zard for Class K fir es is 30 ft (9.15 m). 329

SECTION 2: Building Systems and I-ire Protection Systems

Distribution for ClassC Hazards Extingu ishers with a Class C rating are installed where there is live electrical equipment. This type of extinguisher contains an agent that is electrically nonconductive, usually carbon dioxide, dry chemical, or halogenated agent. New water mi t extinguishers are listed with a Class Crating becau se the}' use distilled water and pass the listing criteria. Once the power to live electrical equipment has been disco nn ec ted , the fire becomes a Class A or Class B fire, depending on the nature of the burning elec trical equipmen t and the burning material in the vicinit}'.

Distribution for Class D lazards lt is particularly important that th e proper exting uish ers be available for Class D fires. Because the properties of combustible metals differ, even a Class D dq 1 powde r ext inguishin g agent can be hazardous if it is used on the wrong metal. Agents shou ld be chosen carefully according to the manufactur er's recommendations. TI1e arnoun l of dry powder agent needed normally is figured according to the sur face area of th e metal plus the form of the metal, which can contribute to lh e severity of the fire a nd cause the agent to "bake off." For example, fires in magne sium powder are more difficult to put out than fires in magnesium shavin gs or ch ips, so more age nt is needed for fires in magnesium powder. TI1emaximum travel distance to all extinguishers for Class D fires is 75 ft (23 rn).

TYPESOF FIREEXTINGUISH RS Listed fire extinguishers are classified into seven major t)'pes. These are stored pressure water extinguishers, dry chem ical e;..,.1inguishers, halogenated agent extinguishers, carbon dioxide extinguishers, foam extinguishers, wet chemical extinguishers, and dry powder extinguishers int ended for use on combustible meta ls. Stored-pressure water extinguishers use plain water as the agent, wilh stored pressure in th e same chamber as the 21-3).Loaded stream extin water (FIGURE guishers are stored-pressure water -based extinguishers that include antifreeze solutio ns for use in low-t empera ture applications. An additive consisting of alkali -metal sa lt solutions-the loaded strea m-is added to the water. These exti ng uish ers usually have a 2.5-gal (9.5 -L) capacit}' and a rating of2 -A. 330

,,,- Carrying handle +--+-Anti

_,___

Discharge hose and nozzle assembly

__

-overfill tube

Water or antifreeze solution

.,____ Siphon tube

FIGURE 21-3 Stored-p ressure water extinguisher. Source : t/FPA 10,2010 , FigureD.4 .1.1.

CHAPTER 21 : Portable Fire Extinguishers

Dry chemical extinguishers are the {Nozzle stored-pressure type or the cartridge- or Discharge cylinder-operated type (FIGURE 21·4 and ..--,--- ,ever FIGURE 21-5). Dry chemical extinguishing -~~~...Carrying agents include ordinary dq r chemical, which ~ handle is sodium bicarbonate- based; multipmpose 11~ Locking ringpin dry chemical, which is monoammonium phosphate-based; or dry chemicals with the Dry other base ingredients of potassium bicar- chemical bonate, potassium chloride, and urea-based potassium bicarhon,1t . Siphon tube Halogenated agent extinguishers are the stored-pressure type (FIGURE21-6). TI1ey contain either Halon 1211 as the extinguishing agent or one of the halocarbon agents. Halocarbon agents include hydro- FIGURE21·4 Storedpressuredry chemical extinguisher.Sou1ce: NfPA10,2010,figureD.4.5(J). chlorofluorocarbon, hydrofluorocarbon, pertluorocarbon, and tluoroiodocarbon. When using this type of extinguisher in confined spaces, prePuncturing cautions should be taken to avoid lever breathing the gases or vapors that are released. The agent is very "clean" (i.e., it leaves no residue), Gas cartridge which is useful when it is used on electronic equipment. Ratings for halogenated agent extinguishers Drychemical are for Class B and C fires. However, larger units may carry Class A ratings. Halon 12 11 has been linked to the destruction of Earth's stratospheric ozone layer. The global FIGURE21·5Cartridge-operated dry chemical extinguisher.Source: NfPA10,2010, FigureD.4.5{b). production ofhalous is controlled by the Montreal Protocol; cur rent supplies of halons are severely limited. New installations of extinguishers where a clean agent is needed are selected from the available halocarbon agents. Existing installations of Halon 1211 extinguishers should continue to follow the requirements in NFPA JO for .inspection, maintenance, and hydrostatic testing. Carbon dioxide extinguishers use steel cylinders rated for 1800 psi (12.4 MPa) or higher (FIGURE 21-7). T11ecarbon dioxide is stored as a liquid in the cylinder with a vapor space at the top. When the agent is discharged, it vaporizes quickly, so the range is relatively short - 3 to 8 ft (1 to 2.4 m). Carbon dioxide is a nonconductor of electricity and is effective on Class B fires. Typical ratings range from 5-B:C to 20-B:C. 33 1

SECTION 2 : Build ing Systems and Fire ProtectionSystems

Foam fire extinguishers are eiPressure ther the stored-pressure type or the gauge cylinder-operated (wheeled) type and rca rrying handle are intended for use on Class B fires but are also eflective on Class A fires (FIGURE 21-8). They contain an aqueous film-forming foam or film-forming fluoroprotein foam solution as the +-1- - Halon 1211 agent. 1l1e2.5-gal {9.5-L) stored-pressure units are rated 3-A:20 to 40-13. Discharge hose TI1e33-gal ( I 25-L) cylinder-operated and no22le units, rated 20-A:160B, are provided on wheels and are most commonly 14--+-- Slphon lube used in airports and i.n factories and warehouses. Wet chemical extinguishers arc FIGURE 21-6 Halon 1211and halogenated available in 1.5 gal (6 L) and 2.5 gal agent- type stored-pressure fire extinguisher. (9.46 L) sizes and are rated for Class Sourc e:NrPA I0, 2010,FigureD.4 .4.1. K fires (no numerical rating). 'TI1e extinguishing agent is a solution of water and potassium acetate, water Discharge and potassium carbona te, or water lever and potassium citrate, or water and a combination of these chemicals. TI1ese extinguishers are intended for Class K cooking oil Ii.res but are dioxide In also eftective on Class A fires. TI1e aCarbon fluid slate wet chemical agent is discharged from the extinguisher as a fine spray Discharge and chemically reacts with the fats horn in the cooking oil to create a thick foam blanket (saponification), which extinguishes the fire and prevents reignition. Dry powder extinguishing agents for use on combustible metals can be applied from an extinguisher, a scoop, or a shovel. 'Ille metals FIGURE 21-7Carbondioxide extinguisher. Source: /JFP A 10,2010 , Figu reD.4.3 (a).

on which these extinguishers and agents can be used are specified in the individual listings and on the extinguisher label. Examples of the different classification s and ratings of portable extinguishers are shown in TABLE 21-4.TI1e proper application of the extingu ishers is illustrated 21·9. in FIGURE 332

CHAPTER 21: Portab!e I-ire Extinguishers

P

TION, MAIN ENANC HYO O ATIC ESTING

Inspection a.nd maintenan ce have very specific meanings within the context of portable fire extinguishr Carrying ers. According lo NFPA 10, an "inhandle spection" is a qu ick check intended to provide a reasonable assurance Anti-overfill that an extinguisher is avc1ilable,is tube full)' charged, and is operable. This consists of determining if the exPremixed tinguisher is .in its designated place, solution that it has not been actuated or tampered with, and that there is 110 obvious physical dc1mageor condition that would prevent its operation. "Maintenance;'in contrast, isa thor- Air-aspirating ~------, '--- Siphon tube foam nozzle ough examination of an extinguisher intended to give maximum assurance that it will operate effectively and safeFIGURE21-8Stored-pressure AFFFor FFFPliquid ly. Maintenance includes a thorough extinguisher.Sou1ce: NFPA 10,2010 , figweD.4 .2.l. examination and any necessary repair or replacement.lt normal!)' will reveal the need for hydrostatic testing. 111c manufacturer provides specific inst ructions regardiJ1gperiodic examination and maintenance.

xamples of ExtinguisherClassifications and Ratings Description 2.5 gal (9.5 L) water, stored pressure 20 lb (9.1 kg) carbon dioxide 5 lb (2.3 kg) dry chemical (ammonium phosphate)

Rating 2-A

10-B:C 2-A:I 0-B:C

10 lb (4.5kg) dry chemical ( odium bicarbonate)

60-B:C

10 lb (4.5 kg) dry chemical (potassium bicarbonate)

80-B:C

125 lb (56.7kg) dry chemical (ammonium phosphate)

'10-A:240-B:C

33 gal ( 125 L) aqueous film-forming foam

20-A:160-B

5 lb (2.3 kg) Halon 1211

10-B:C

9 lb (4.1kg) Halon 1211

I-A:I0-B:C

1.5 lb (0.68kg) Halon 1211/130 1

I-B:C

333

SECTION 2 : Build ing Systems and Fire Protection Systems

For Class A types

For Class A, B types

For Class 8 , C types

For Class A, B, C types

For Class K types

For Class D types

Note: Recomme nded colors, per PMS (Pan tone Matching System) include the following:

BLUE-299 RED -W arm Red

FIGURE21·9 Recommended marking system.Source: NFPA 10, 2010,Figu1e B.1.1.

J\IIaintenance must be performed annuaUy by a servicing company or by a trained industrial safety or maintenance person . NFPA 10 Annex Section A.7.3.2 offers a list of over 20 items that need to be reviewed, checked, and noted during this yearly activity. NFPA 10 (NFPA 10, Section 7.1.2) requi res personnel who perform the mainte nance and recharging duties to be certified. This proves familiarity with the minimum requirements for selection, placement, and servicing of portable fire extinguishers. Organizations offering these tests online vary from national extinguisher wholesalers to bui ldin g code organizations. It is important for the technician to make sure that the certification program is recognized by the AHJ prior to taking the test. A letter 334

CHAPTER 21: Portable I-ireExtinguishers

from facility management is used as the certification document for industrial safety or mainten ance personnel (see NFPA 10, Section A.7.1.2.1.2). Cartridge-operated, q 1w1der-operated, loaded stream, and pump tank extinguishers are the only types that are required to be examined internally on an aimual basis. Extinguishers with a 5-year hydrostatic test interval are examined internally on the same 5-year basis. TI10sewith a 12-year interval are examined internallyon a 6-year basis. Nonrechargeable extinguishers are neither examined internally nor hydrostatica!Jy tested. 1 hey are removed from service 12 years from the date of mannfacture. :Maintenance tags or labels must be attached to fire extinguishers to indicate the month, the year,and the identification of the person and company performing the service. A separate label is required to record information on the 6-year teardown requirement. "Hydrostatic testing" is performed by personnel who have been specifically trained. Untrained people should not attempt the procedure because serious safety hazards can easily develop. TI,e pu rpose of hydrostatically testing fire extinguishers is to protect against the unexpected failure of the cylinder. ·1he test intervals for fire extinguishers are provided in TABLE 21-5. The cylind ers of high-pressure extinguishers that pass the hydrostatic test must be stamped with the month and year of the test and the Department of Transportation identification number. Low-pressure extinguishers are not stamped, but a

HydrostaticTest Interval for Extinguisher Extinguisher Type

Stored-pressure water,loadedstream, and/or antifreeze Wetting agent AFFF(aqueous film-formingfoam) FFFP(film-formingnuoroprotein foam) Drychemical with stainless steel shells Carbondioxide Wet chemical Drychemical,stored-pressure, with mildsteel shells,brazedbrassshells,or aluminum shells Drychemical,cartridge- or cylinder-opera ted, with mildsteel shells Halogenated agents Drypowder, stored-pressure,cartridge- or cylinder-operated,with mild steel shells

Test Interval (years) 5 5

5 5

5 5

5 12 12 12 12

Note: Stored-pressurewater extinguisherswith liberglassshells(pre-1976)are prohibited from hydrostatictesting becauseof manufacturer's r call.

335

SECTION 2: Building Systemsand Fire Protection Systems

self-destructive label indicating the month and year of the test and the identification of the person and company performing the test is affixed to the cylinder. Inspection, maintenance, and hydrostatic testing must be carried out according to the minimum requirements established in NFPA 10 and in strict conformance with the manufacturer'srecommendations. ]11eminimum frequency for inspections is at 30-day intervals.

RAPHY Carson, W G., and Klinker, R. L., FireProtectionSyste111s: Inspection, Test nnd Mninte11n11 ce J°vlnnunl,3rd ed., NFPA, Quincy, MA, 2000. Cote, A. E., ed., FireProtection1-lnndbook,20th ed., NFPA, Quincy, MA, 2008. "Rating and Fire Testing of Fire Extinguishers;' Fire Protection Equipment Directo1y (issued annually), UL/ANSI 711, Underwriters Laboratories/ American National Standards Institute .

NFPACodes, Standards, and Recommended Practices See the latest version of the NFPA Catalog for availability of current editions of the following documents. NFPA 1, Fire Code NFPA 10, Stnndnrdfor PortnbleFireExtinguishers NFPA 13, Stnndnrdfor tile Jnstnl/ntio11 of Sprinkler Systems NFPA 30A, Codefor Motor Fuel DispensingFncilitiesnnd Repnir Gnrages NFPA 32, Standardfor D1yclenni11g Plnnts NFPA 58, Liquefied Petroleum Gns Code NFPA 86, Stn11dnrdforOvens and Furnaces NFPA 96, Standardfor \fentilntion Control nnd Fire Protectionof Com111ercinl Cooking Operations NFPA 101®, Life Safety Code® NFPA 120, Standardfor FirePreventionnnd Control in Con!1\tlines NFPA 122, Stnndnrd for Fire Prevention and Control in Metn/!No11metalMining nnd Metal lv1i11eral ProcessingFacilities NFPA 302, Fire ProtectionStandnrdfor Pleasureand Co111111ercinl Motor Craft NFPA 303, FireProtectionStn11dnrdforMnri11nsand Boatyards NFPA 385, Standardfor Tn11kVehiclesfor Fln111111nble and CombustibleLiquids NFPA 407, Stnndardfor Aircraft Fuel Servicing NFPA 408, Standardfor Aircraft Hn11dPortnbleFireExtinguishers NFPA 410, Stn11dnrd011Aircmft Mni11tena11ce NFPA 418, Stn11dnrd for Heliports NFPA 430, Codefor the Storageof Liquid n11dSolid Oxidizers NFPA 498, Stmuinrd for Safe 1-lnvensand Interdw11geLots for \fehicles Transporting Explosives NFPA 1192, Stnndnrd 011Recrentim1nl\lehicles NFPA 1194, Stn11dnrdJorRecrentio11nl\lehicleParks and Cnmpgro1111ds 336

CHAPTER

22 MEANS OF EGRESS Ron Cote, PE

Chapter 7, "Means of Egress;' of NFPA JOI®, Life Sn_fetyCode®, 2012 edition is the most impor tant, fundam ental chapter of the code. 1he occupancy chapters of NFPA 101 draw heavily on its concepts and detailed criteria. A stand-alone chapter on inspecting the means of egress might be a cornerstone around which the life safetyrelated portions of the Fire and Life Safety Inspection Manual (the manual) could be structured. However, the occupancy chapters of the code specify a comprehensive life safety package made up of a measured mix of egress, fire protection, building service, and interior finish requiremen ts. Thus, no one should inspect onl>' the means of egress. The occupancy chapters that follow in this manual correctly stress that the means of egress is only a part of the life safety package and that the package needs to be inspected as a whole. TI1e following sections in this chapter highlight !he facets of a life safety S) Stems inspection that relate specifically to the ineans of egress. 1

INSPECTION TYPES An inspect ion of the means of egress needs to be tailored to the purpose for which the inspection is being cond ucted. TI1einspection might be for any of the following purposes: 1.

Determining code compliance with the egress provisions in a jur isdiction that has adopted, for the first time, a given code-s uch as NFPA 101®, Life Safety

Code®. 2. Signing off on the egress portion of a new construc tion or renovation project so that the certificate of occupancy can be issued. 3. Investigating the validity of a claim that the means of egress has been compromi sed by building operators . 4. Ensuring via periodic reexamination that code-compliant, egress-related features and systems are properly maintai11ed.

SECTION 2: Building Systems and Fire Protection Systems

5.

Verifying that egress -related code deficiencies that were not ed during an earlier inspection have been corrected .

ALL- INCLUSIVE INSPEC IONS Inspections conducted for the purposes of items l (determining compliance on a newly adopted code) and 2 (signing off on a new construction or renovation project) are part of all-inclusive examinations and evaluations that involve plan review, calcu lations, and the application of detailed code criteria. Such inspec tions are beyond the scope of this texl. The preparation needed for all-inclu sive inspections should include on-the-job trainin g under th e supervision of an experienc ed inspec tor, seminar attendance, and extensive studying of reference materials such as the Life Safety Code®

Handbook.

REINSPECTIONS Inspections conducted for the purposes of the above items 3, 4, and 5, which are all basically reinspections, involve the following: Preparing oneself with a working knowledge of the code requirements against which the facility's means of egress features need to be compared. 2. Assuming that th e earlier comprehensive inspection, such as that conducted for purposes of issuin g the certificate of occupancy, ensured that the means of egress system was adequately sized (e.g., that its capacity does not need to be reevaluated provided that other features and uses have not changed). 3. Allowing intuition and gut reaction to serve as cues for when to stop and pay attention to a potential problem area . 4. Identifying egress uses, practices, elements, and systems that might have changed s.ince the facility was last inspect ed. 5. Assimilating the effect that the changes have imposed on the overall level oflife safety provided by the means of egress system prior to the changes. 6. Incorporating the evaluation of the means of egress system into the overall inspect ion that will be complete only when it also includes consideration of the fire protection , building service, and interior finish req uiremen ts required by the appropriate occupancy chapters of the code. 1.

FAMILIARITYIN INSPECTIONS Familiarity with a given facility, such as that gained by having conducted the recent periodic inspections of that building, will often make the inspection process easier. The inspector who is familiar with a facility experiences fewer distractions by factors unrelated to the inspe ction task. Observations can be more focused. An inspector who has previously visited th e faciliLycan more easily identify changes caused by reuse of the space, minor renovation s, or laxne ss in housekeeping. The inspector, however, needs to guard against the complacency associated with feeling too much at home within a facility. Also, a sole in spec tor at a given building 338

CHAPTER 22: Means of Egress

might fall into the trap of focus ing heavily on subjects of personal int erest whil e ignorin g eq ually important subje cts with whi ch he o r she ha s limi ted interest or ex per tise. An eflective inspect ion process migh t use two insp ectors on an alternat ing basi s for one facility Each inspector would vis it the site often enough to retain familiarity , yet no t so often as to lose the inquisitiv e drive tha t often accomp an ies a new assignm en t. ln effect, the two inspectors would see thin gs through two differe nt pair s of eyes and would evaluat e them using two different exp erie nce bases.

EFININ

MAN

0

G ESS

1he mea ns of egres is everywhere, not jus t at the exit doors. It consists of the exit access, the exit, and th e exit d ischarge. 'lh e exit access cover s the vast majority of the floor area that serves the three-part mean s of egress. Jt is difficult to justify excluding any usable floor area from bein g within the egress system . Thus , a thoroug h inspec tion of th egress system ne essilaie. viewing all buil d ing areas that occupants can be expected to occupy under both emerg ency and nonem ergency uses.

Inspect ion Walk-Throughs During each insp ection, a complete walk -th roug h will typically be needed. Even if the exit doors al the front of the building are correc tly maint ained in an unlo cked con dition, the insp ec tor should not assum e that the door s at the rea r of the facility are similarly maintained . TI1e doors at the rear might no t be used on a day-to -day basi s. They .ilso create secur ity p roble ms beca use they are not watched as easily as are th e door s at the main entra nce. Thus, they are more pron e to being locked. Jf the egress path s are maintained clear and unobstrn cted in one wing of the build ing , the in spector should not assum e that the egress path s in ano ther wing are similarl}' maintain ed. ·n1e orderliness noted in o ne area migh t be the result of one individual's or one department' s efforts and mi ght not reflect an enfor ced, facility-w ide manag ement policy. An eflective inspection of the egr ess system can be made only by phys ically tra versing the myriad travel paths availabl e to th e building occu pant s. TI1ese paths also include those at the outside o f the building that serve as exit disc harge by con nect ing the exit to th e public wa y. An inspec tion co ndu cted in the summer in a locale know n for its debilitating winter snow storms canno t acc urately eval uat e whether th e exter ior exi t discharge path s will be kep t usable throu gh ou t th e year, especially for tho se path s th at are not used 0 11 a daily basis but are prov ided exp ressly for emergency egre ss.

Inspect ing Out-of -Sight Features Some of the egress path s, such as those within exit stair enclosures, might not be used on a day-to -day basi . The stair enclosu re that is not used regularly typically loses its eflect iveness as an egres s path und er two scenarios. The space is seen by occupant s as unneed ed, which leads to ii becoming a catch- all for the storage of items used

339

SECTION2: lluilding System s and Fire Protection Systems

infrequently, or it becomes strewn with litter by occupants who make unauthorized use of the area, for example, for smoking breaks. Various building features that serve as part of the required means of egress extend above suspended ceilings and cannot be inspected simply by walking through the occupied spaces of the building. A smoke barrier, if it is to do its job of preventing the migra tion of smoke from one smoke compartment to an adjacent compartment, must be cont inuou s so as to run vertically from the floor slab to the underside of the floor or roof deck immediately above . 'fo perform a proper inspection, the inspector will need to climb a ladder, remove a lay-in ceili ng tile, and check above the ceiling for penetrations in the smoke barrier wall. 'D1e most common place to make penetrations in a smoke barrier is above the ceiling, where cables and conduit are typically hidden from the view of building occupants. TI1eabsence of penetrations in the portions of the smoke bar rier that are positioned below the ceiling cannot be relied on as evidence of barrier continuity above the ceiling . Ad equ ate proof for con siderin g a doo r to be a fire door usuall}' rests with a lab el on the door that attests to the door's listing as a fire door by a recognized testing laboratory. If the inspector cannot see the listing label from the floor, he or she should not automatically assume that the door is not a fire door. Such labels might have been in sta lled on the top edge of the door. Limited ceiling heights might prevent the ins pec tor from standing on a ladd er and looking down on th e top edge of the door. 1he experienced inspector will, the refor e, carry a small pocket mirror to ascertain the presence of, and informat ion contained on, the fire door label attached to the top edge of the door.

MEANS OF EGRESSINSPECTION

METHODSAND ASPECTS Visual Observations When inspecting the means of egress, visual observations alone are not adequate. If a building feature is meant to be operated, the inspector needs to operate it. For example, a seldom-u sed egress door located in a wall at th e building perimeter will often have seized up within its frame in such a way that the average building occupant cannot exert th e force necessary to free the door so that it can be opened. Where a door has been equ ipp ed with delayed egress hardware, the inspector needs to test the specialized un locking system operationally. • Does pushing on the release device for 3 seconds initiate an irreversible process that permits the door to be opened after 15 seconds? • Does an audib le indi cator at the door begin to sound at the end of the 3-second period to signify to the occupants that the system is functioning as intended? • Does th e door remain unlocked afte r it has been opened and closed? TI1e inspector needs to confirm all these features by physically exercising the unlocking mechanism, not just by visually observing it.

340

CHAPTER 22: Means of Egress

Quantitative Versus Qualitative Evaluation TI1einspector can often evaluate the open ing force required for a given door against the maximum values specified by the code without having to measure the force with a scale. To the experienced inspector, the door opening force either feels right or it does not. However, where performance is suspected to be marginal, the inspector will need to use more quantitative methods. An inspection report citing that the door opening forces seem to be excessive will not be as convincing as one that establishes, for example, that the 35-lb force (155 N) that was measmed during the inspection i in exce of the 30-lb force (133 N) permitted b)' NFPA JO/® for sett ing the door in motion once the latch has been r t racted. The inspector, when visiting a factory where the placement of new manufacturing equipment and mechanized conveyor lines has changed the egress path, might deter mine that the travel distance needs to be evaluated . In measuring the travel distan ce to the nearest exit, the inspector might pace off the distance using an exaggerated step tha t, th rough expcri 11 e, ha been honed to be an accurate indicator of 3 ft ( I rn). In a warehouse, the inspector might make use of the fact that the columns supporting the roof structure are spaced 011 40-ft (I 2-m) centers and might thus count the number of columns encountered along the egress path. In an office setting, the inspector might estimate the travel distance by counting the number of consistently sized, 2-ft (0.6-m) ceiling tiles positioned above the egress path. Each of these methods helps the inspector to avoid having to lay a tape measure at floor level along the actual path of travel.

Role-Playing 111einspector needs to role-play so as to ensure that the needs are met of all persons whom the code requirement s are intended to serve. For example, in checking opening forces for a side-h inged and swinging door, the inspector sho uld steµ into the smoo thsoled shoes of a small person with low body weight and should not assume the role of a professional football linebacker with shoe cleats for added tract ion. In role-playing, the inspector needs to guard against creati ng new requ irements that are in excess of those that the inspector has been charged with using. In some cases, the minimum requirements as codified might not ensure that eveq' possible building occupant will be able to open an exit door. For example, persons with disabilities that force them to travel by wheelchair might not be able lo exert the 30-lb force (133 N) permitted by the code for setting the door in motion once the latch has been retract ed. If the inspector works directly for the building operator and is given some latitude to evaluate the egress system against the needs of the neediest occupants, a recom mendation to do more than that required by code might be in order. 'Il1e inspector needs to keep in perspective the fact that codes, by their very natur e, are compilations of minimum requi reme nts.

Timing of Inspections TI1etiming of inspections depends on the use of the facility being inspected. For example, when evaluating whether a nightclub, rumored to be overcrowded, is ~perating 341

SECTION2: Building Systemsand Fire Protection S~•srems

with occupant loads in excess of the posted maximum, the inspector will need to visit the fi:,cilityat night. An inspection dur ing the inspector's normal daytime shift will not answer the question. In another example, when determining whether the required minimum widths of egress aisles in a department store are being maintained , the inspector should visit the store in mid-Dec ember when it is stocked to its fullest extent during the end-of-year holiday sales period. In an atrium building that uses the balconies and walkways within the atrium as part of the requ ired means of egress, a smoke-control system might be required by code. TI1esmoke-control system becomes a feature that needs to be inspected as part of a means of egress inspection. The inspection and testing of a smoke-control system is complicated and time-consu ming. It is often done after normal business hour s when the building has its lowest occupancy level. 'TI1epresence of building occupants typically is not needed for a realistic smoke-control illspection. However, where the system is designed to rely on pressure differentials at barriers to control the migration of smoke, it might be necessary to wedge a door ope n to simu late the etfect that an open door would have while it is being used, for example, by 150 occnpants as part of the egress path. Not all means of egress leatu res can be evaluated by an instantaneous observation or measurement. Sometimes an elapsed-time inspection is needed. TI1eemergency lighting provisions conta ined in NFPA JOJ® require that an annual test be conducted on battery-powered emergency lighting systems for not less than 1½ hou rs. The initial illumin ation level and a degraded level at the end of the 1½ hours must be measured. The inspector will need to be present, at a minimum, for the beginning and end of the test.

Rank- Ordering Code Violations The product of a good inspection of the means of egress is a report from which informed actions can be taken . Code violations or deficiencies need to be rank-orde red in terms of importance. A locked egress door and an inoperat ive light bulb in an exit sign are not equal deficiencies; they have potential for very different effects on the safe egress of building occnpant s. Proposed solutions, their estimated costs, and ana lysis of the effect they will have on the overall life safery are additional features that will help to make the inspection report a useful tool for change.

BIBLIOGRAPHY Cote, R., Harrington, G., ed., Life Safety Code®Hmrdbook,NFPA , Quin cy, MA, 20 12. NFPA Codes, Standards, and Recommended Practices

Sec the latest version of the NFPA Catalog for availability of the current edition of the following document. NFPA JOJ®, Life Safety Code®

34 2

CHAPTER

23 INTERIOR FINISH, CONTENTS, AND FURNISHINGS Kristin Collette Bigda, PE, MSFPE

Interior finishes have been a significant factor in rapid flame spread for many of the deadliest fires in the last century. Inspectors, therefore, must be constantly aware of the different types of interior finishes that can be installed within a building. Interior finishes trad itionally are considered to consist of those materials or combinations of materials that form the exposed interior surfaces of walls, ceilings, and floors in a building. Interior floor finishes, specifically, are those exposed surfaces of floors, ramps, stair treads and risers, and other walking surfaces, and may be applied over or in lieu of a finished floor. Interior wall finish is the interior finish of column s, fixed or movable walls, and fixed or movable partitions. Furni shings, which in some cases may be secured in place for functional reasons, should not be considered interior finish. Decorations and furnishings generally are not considered interior finishes but are handled separate ly. Furni shings are addressed later in th is chapter. Interior finish relates to a fire in four ways. It can affect the rate of a fire build-up to flashover conditions, contribute to fire extension by flame spread over its surface, add to the intensity of a fire by contributing additional fuel, and produce smoke and toxic gases that contribut e to the life safety hazard and property damage potential. Controlling the type of interior finish in a building based on occupancy type will ultimately increase the occupants' safel)'.

WALLAND CEILING FINISHES Interior wall and ceiling finishes are the exposed interior surfaces of buildings, including, but not limited to, fixed or movable walls and partitions, columns, and ceilings. Types of interior finish materials are numerous and include some commonly used materials such as plaster, gypsum wallboard, wood, plywood paneling, fiber ceiling tiles, plastics, and a variel)' of textile wall coverings.

SECTION2: Building Systems and Fire Protection Systems

For proper evaluation classifications, assemblies of interior wall and ceiling fin ishes should be tested under conditions that simulate their actual in sta llation. If they are no t tested under such conditions, the test findings may not be accurate. For example, the flame spread rating of an interior finish material tested without the adhesive that is actually used to apply it may be more favorable than it is when the adhesive is used. 'The type and end use of a m ateri al is used to determine the fire test it will undergo . A material that is used as a wall covering must have both a flame spread index rating and a smoke developed index rating. The same material used as a drap e or a curtain mu st be evaluated to determine its flame propagation res ista nc e throu gh a vertical burn propagation test protocol. And if the material is used on upholstered furniture, it must undergo an appropriate fire test for resistance to cigarette ignition. There is no correlation between the three tests; thus, satisfactory performance from one test cannot be used to draw conclusions about the materials for an)' other purpose. Carpets and similar car pe t-like materials canno t be arbitrarily app lied to walls or ceilings . TI1ese materials may behave well from a fire development perspective when applied to floors, but when they are either oriented vertically or mounted on a ceiling, many will perform poorly. To be approved or permitt ed to be used as a textile wall or ceili ng material, the material must be evaluated as a wall or ceiling covering rather than a floor covering. Fire test methods and approved applications for textil e, expanded vinyl, and foamed plastic coverings are addressed later in this chapter.

Flame Spread and Smoke Developed Indices Interior wall and ceiling finishes are generall)' classified in accordance with the results of actual fire tests, which record the flame spread and smoke development of the material. Flame spread ratings offer a general ind ication of th e relative rate at which fire may spread across the surface of the material; smoke deve lopment is the degree of visual obscurity observed during this test. TI1e tests used for wall and ceiling finishes t)1pically are measured in the Steiner Tunnel Test, also known as American Society for Testing and Materials (ASTM) E-84, Standard Test lviethod for Su,fa ce Burning Charnc/eristicsof Building Materials, and American National Standards Institute/Underwriters Labora tories (ANSI/UL) 723, Standard for Testfor Swface B11rni11g Characteristicsof Building 1\tlaterials. In this test, a 24-ft (7.3-m) long by 20-in. (51-cm) wide sample is mounted to the top of a 25-ft (7.6-m) long "tunnel''. A gas flame is ignited at one end, and a regulated constant draft is maintain ed through the tunnel. Flame front progress is observed through side windows for a 10-minute period . Onc e the flame front pro gress ha s been charted, the area under a time-distance curve is used to determine th e material's flame spread ind ex. The flame spread index represents the relative ra te at which flame spreads across th e surface of this material compared with its spread across the surface of inorganic rein forced cement board and red oak flooring, which exhibit flame spread indi ces of O and 100, respectively .

344

CHAPTER23: Interior Finish, Contents, and Furnishings

TI1eflame spread and smoke developed rating is indexed into three ch,ssification as follows: Flame spread index

Smoke developed index

ClassA 0 to 25

Oto 450

ClassB: 26 to 75

0 to 450

ClassC: 76 to 200

0 to 450

The smoke developed index is based on obscuration; that is, on the ability to "see" illuminat ed exit signs, Smoke developed indices are derived from the flame spread evaluatio n of the Steiner Tunn el Test. The degree of smoke obscuration is measured by a photoelectric cell mounted opposite a light source in the tunnel venl pipe. Reduction in light caused by passing smoke and particulate is read and recorded b)' the photoelectric cell, and this information is used to calculate the smoke developed inde x. The num erical value of 450 was chosen a the point at which ihe means of egress may become obscured. An interior wall and ceiling finish material with a low smoke developmen t value should provide better visibility in a given egress route than a material with a high smoke developm ent value. Given that the smoke development value .is a cumulative measurement over the prescribed test duration, it is based on both quantity and rate of smoke liberation, Some codes refer to Classes .A, B, and C as I. JI, and III, but the flame spread and smoke developed ratings are the same. Occupancy classification dictates the permitted interior finish classifications. As indicated earlier, the clas ification of an interior finish is that of the basic material used either by itself or in combination with other materials. TI1ematerial should be tested in exactly the same configuration in which it will be used in a facilit) '· NFPA JOI®, L~feSnfety Code®, requ ires the use of specific classes of interior wall and ceiling finish materials, which are differentiated by their allowable flame spread index, based on consideration of their installed location within the building, the building's egress paths, and the occupancy in question. Different classes of interior finish materials are specified for an office area, for example, as opposed to an exit stair enclosure or exit access corridor. TI1edifferent classes recognize that, when escaping a building, people must move away from the flames while traveling through the means of egress toward an exit. TI1eclasses of interior finishes that are considered acceptable within an open office, therefore, are different from those that are required for exit enclosures. Paint or wall coverings applied after the interior finish has been installed are not subject lo interior finish requirements if the)' are no thicker than 1128thof an inch. However, such materials would require a flame spread rating index if they or their applications produced significant flame spread or smoke development in and of themselves. Multiple layers of wall coverings can contribut e to a rapid fire growth and should be subject lo the requirements for the interior finish of the type of occupancy in which they are used (FIGURE 23-1).

345

SECTION 2: Building Sy,tems and rire Protection Systems

FIGURE 23·1DuPont Plazahotel fire. Rapid fire growt h was, in part, caused by the wall finish in the room of origin. Sou rce:LifeSafe ty(ode®Hol/dbook, NFP,\, 2000, Exhibi t l0.1.

Textiles, Expand ed Vinyl, and Cellular or Foamed Plastics TI1e application of textiles and expanded vinyl materials as wall and ceiling finishes is truly limited. If the materials are rated as Class A when tested in accordance with ASTM E-84 or ANSI/UL 723, they may be used as wall or ceiling finishes under any one of the following circumstances: • In areas protected by approved automatic sprinkler systems. • On partial height partitions no greater than three-fourths of the floor-to-ceiling height or less than 8 ft (2.4 m), whichever is less. • Where the finish item extends no more than 4 ft (1.2 m) from the floor. • Where previously approved. Two alternative tests protocols now exist for evaluation of all interior finish materials, including textile materials, expanded vinyl and some of the cellular/foamed plastic materials. NFPA 265, Standard Methods of Fire Testsfor EvaluatingRoom Fire Growth Contribution o_{Textile WallCoveringson FullHeight Panelsand Walls,is now a nationalJy recognized room -corner fire test to be used specifically for textile and vinyl wall coverings. If the sample, when mounted as intended, passes this test, its use on walls and partitions is permitted. An additional nlternative test for interior finish applications is NFPA 286, Standard lvfethodsof Fire Testsfor Evaluating Co11trib11tion of Wall 346

CHAPTER23: Interior Finish, Contents, and Furnisl1in gs

and Ceili11g InteriorFinish to Room FireGrowth.NFPA 286 was developed specifically to measure the extent of flame spread and burning relative to the realisticallysized and mounted sample, whether flashover occurs, the peak rate of heat release, and the total smoke released throughout the test. The application of cellular or foamed plastic materials on interior walls and on ceilings should not be permitted unless fire tests can reasonably substantiate the combust ibility characterist ics of the materials for the particular uses under actual /-ireconditions. Cellular or foamed plastics may be used as trim if they do not exceed 10 percent of the wall or ceiling.

Trim or Incidental Fini h Trim or i.ncidental finish applied to interior walls or ceilings may be of a Class C ma terial, even when the interior wall or ceiling finish is required to be of a Class A or B material, as long as they are not applied to more than 10 percent of the aggregate wall area. ·n1e purpos e of this provision is to permit the use or wood Irim around door and windows as a decoration or as functional molding, because this type of trim would be distributed uniformly throughout a room rather than concentrated in one area.

Fire Retardant Coatings Interior finish materials that do not have the appropriate interior flame spread rating can be modified by applying fire retardant coatings. These coatings must be applied iu accordance with the manufacturers' instructions and should possess the desired degree of permanency, remaining effective when in actual use. Most fire retardant paints and coatings require an application rate three lo four times greater than that of ordinary paints. The treatment must be reapplied or renewed periodically, because the retardant's overall effectiveness could be reduced by regular maintenance, washing, or cleaning. Fire retardant treatments should comply with the requirements of NFPA 703, Standardfor Fire Retardm1tImpregnated \,Vooda11dFire RetardantCoatings for BuildingJ'vfaterials.

INTERIOR FLOOR FINISHES Interior floor finishes are the exposed floor surfaces of a building, including coverings, that are appli.ed over the normal finished flooring or stairs, including risers. To obtain a rating for interior floor finishes, the Flooring Radiant Panel Test Method is used. This test method is also known as NFPA 253, Standard lvfethodof Test.forCriticalRadim1t Flux of FloorCoveringSystems Usinga Radiant Heat EnergySource,and ASTM E-648, Sta11dardMet/rodof Testfor Critical Radiant Flux of Floor CoveringSystems U~i11g n Rndim1tHeat E,1e1gySource. The test measures burning that occurs on a sample. The results are then converted into a value, known as the "critical radian! flm,:' of Watts per square centimeter. A Class I interior floor finish has a cr itical radiant flux of at least 0.45 W/cm 2, and a Class II interior floor finish has a minimum 0.22 W/cm2. The greater the critical radiant flux value, the more resistant the floor fii1ishis to ignition and flame propagation. 347

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Since April 1971, the federal government has required that all carpets manufactured in the United States meet a flammabilit)' standard known as the Federal Flammability Standard, FF-1-70 Pill Test, or simply the Pill Test. In the Pill Test, eight 9-in.-square (23-cm-square) sections of a carpet are securecl in a test chamber. A methenamine tablet is ignited and placed in the center of the specimen. Tfthe flame advances to any point within 1 in. (2.5 cm) of the edge of the sample, the specimen fails the test. The approp riate floor finish rating is determined by the way in which the facility is used and the location of tbe finish within the facility; that is, in exits and corr idors. Interior floor finish ratings apply only when floor finish presents an t11msual hazard or where the floor finish requirements are specified based on occupancy type.

AUTOMATIC SPRINKLE S The presence of an automatic sprinkler S)'Stem in a facility provides a degree of safety that i incorporated into the interior finish requirements. 1l1e rating of a wall, ceiJing, or floor finish can be reduced by one level if a sprinkler system is in tailed in the facilit)'· Although floor finish items are permitted to drop to a nomated material, in no circumstance can wall and ceiling finish items be reduced below a Class C rated material.

FURNISHINGS AND DECORATIONS Furn ishings and decorations are not considered interior finishes when one is discussing flame spreacl characteristics. But these items can contri bute fuel to a fire in an occupancy and are required under certain conditions to meet certain fire tests. Several occupancies restrict draperies, curtains, and other loosely hanging fabrics. Only those articles salisl11ing the applicable provisions ofNFPA 701, Standard Methods of FireTests for Flame Propagationof Textiles a11dFilms, are permitted . Upholstered furniture and mattresses also contribute to the fire loading in a facility. Depending on the type of occupancy in which the furniture is placed, it may have to unclergo a fire test. Many different types of tests are available to determine the fire characteristics of upholstered furniture . NFPA 260, Standard Methods of Tests and Classification Syste111 for Cigarette Ig11itio11 Resistanceof Co111po11e11ts of Upholstered Furniture, and NFPA 261, Stnndard Nfethod of Testfor Determining Resistance of MockUp Upholstered Furniture Material Assemblies to Ig11itionby Smolderi11gCigarettes, are just two of these test standards. Depending on the way the occupants use the facility, upholstered furniture may be required to meet a certain threshold for rates of heat release. NFPA 266, Standard Method of Testfor FireCharacteristics of Upholstered Furnit11reE.,1Josedto Fla111i11g lg11ition,provides the necessary testing procedures to obtain these rates of heat release. NfPA 267, Standard Method of Testfor FireCharacteristicsof 1\tfa flressesand Beddi11gAssemblies Exposed to Fla111i11g Ignition Source,provides the test criteria for determinin g heat release rates for mattress and bedding contents. As with interi.or finishes, upholstered furniture need not be tested if an automatic sprinkler system has been installed in the facility.

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BIBLIOGRAPHY ASTM D-635, Sta11dardTest Metliodfor Rate of B11rni11g and/or Extent and Time of Burni11gof Plasticsi11a Horizontal Possitio11 , American Societ)' for Testing and Materials, West Conshohocken, PA. ASTM D-1360, Standard 'lest Metliodfor Fire Retarda11cyof Paints (Cabi11etMetliod), American Society for Testing and Materials, West Conshohocken, PA. ASTlvfD-2859, Standard TestMet/10dfor Fla111mability of Finished TextileFloorCoveri11gMaterials, American Society for Testing and Materials, West Conshohocken, PA. ASTM D-2863, Standard Testlvfet/rodfor Measuring tireMi11i11111111 Oxygen Conce11tmtio11to Support Candle-Like Co111b11stio11 of Plastics(Oxygen Index), Amt:rican Society for Testing and Materials, West Conshoho cken, PA. AST!vlD-3014, Standard Test Met/rodfor Fla111e Height, Ti111e of Bumhrg, and Loss of Weightof Rigid 'fl1en11oset CellularPlastics/11a VerticalPosition, American Societ)' for Testing and Materials, West Conshohocken, PA. ASTJ\tfD-4549, Standard Spec(firntio11 for Po{ystyre11e Molding and Extrnsio11lvfaterials (PS), American Society for Testing and Materials, West Conshohocken, PA. ASTM E-69, Standard Test Method for Combustible Properties of Treated Wood by the Fire-1i1beApparatus, American Society for Testing and Materials, \Vest Conshohocken, PA. ASTM E-84, Standard Test .Met/rodfor S111fnceBurning Characteristics of Building Materials,American Society for Testing and Materials, West Conshohocken, PA. ASTM E-648, Stn1JdnrdTestMethodfor CriticalRadiant Flrixof FloorCo1ering Systems Using a Radimrt Heat Energy Source, American Society for 'Jesting and Ivfaterials, West Conshohocken, PA. Cote, R., Harrington, G., ed., Life Safety Code® Handbook, NFPA, QuinC)',MA, 2012. Cote, A. E., ed., Fire ProtectionHn11dbook,20th ed., NFPA, Quincy, MA, 2008. "Carpets and Rugs-Notice of Standard," Federal Register,Vol. 35, No. 74 (April 16, 1970). Standard for the smface flammability of carpets and rugs (Pill Test). UL 723, Testfor Swface B11mi11g Characteristicsof Building Materials, Underwriters Laboratories, Inc., Northbrook, IL. 1

NFPACodes, Standards, and Recommended Practices See the latest version of the NFPA Catalog for availability of current editions of the following documents .

NFPA 35, Standardfor the Mm111fact11re of OrgnnicCoatings NFPA JOI®, Life Snfety Code® NFPA 253, Standard Met/rodof Testfor CriticalRadiant Flux of FloorCoveringSyste111s Usi11g a Radia11tHeat E11 ergy Source NFPA 255, Standard Method a/Test of Sruface B11mi11g Clrnracteristics of BuildingMaterials NFPA 260, Standard Methods of Tests and ClassificationSystem for Cigarettelgnifio11 Resistanceof Co111po11e 11t s of Upholstered F11mit11re 349

SECTION2: Building Systems and Fire Protectio n System s

NFPA 261, Standard i'vfethodof Testfor DeterminingResistanceof Mock-Up Upholstered

FurnitureNlaterialAsse111blies to Ignition by S1110/deri11g Cigarettes NFPA 265, Standard Methods of Fire Testsfor Evaluati11gRoo111 Fire Growth Co11tribu -

tio11of Textile Wall Coverings NFPA 266, Standard lvlethod of Testfor Fire Characteristicsof UpholsteredFrll'niture

Exposed to Flaming lgnitio11 NFPA 267, Sta11dardMethod of Testfor Fire Chamcteristicsof Mattressesand Bedding

AssembliesExposed to Flaming Tg11itio11 Source NFPA 286, Standard lvlethodsof Fire Testsfor EvaluatingContributio11of Walland Ceil-

i11gInterior Fi11islito Room FireGro,vth NFPA 701, Standard Methods of Fire Testsfor Flame Propagation o( Textiles and Fi/111 s NFPA 703, Standardfor FireRetardant Impreg1111ted Wood and FireRetardant Coatings

for Building Materials

350

CHAPTER

24 COMMISSIONING PROCESSFOR FlRE PROTECTION SYSTEMS 1\ttatthew J Klaus, NISFPE

Commiss ioning of fire p rolectio n and life safety sysle ms can best be de fined as a qua lily con trol process used to ens ure that the systems in place will function as intended. Alt hough commiss ioni ng is com mon !)' be]jeved to be sjm ply the final accepta nce and verification test for the various active systems, the commissioning process in fact be gin s before design drawi ngs are prepared or before grou nd is broken on a project. From its inception on a given proj ect, the process is high ly administrative and procedural while responding to and incorporating field ac tivit ies. 'TI1e commis sioni ng process is ai1ned at developin g a team of individua ls with vary ing ro les and responsi biliti es in the design, construction, and occupancy phases of a building project. This is achieved by performance verification and is demonstrated th rough inspection, testing, and documentation of these activities. The commiss ion ing process varies from the trad ilional concept of testing and start-up, in tha t comm issioni ng begins at project inception and con tinu es lhrough desig n, construc tion , and proj ect closeo ut , and th en throughout th e facility's ope rat ions phase. O ne of the final por tions of the corn missioning p rocess is integrated system testing. Oftent imes, the integra ted S)'Stem testing tha t occurs at the close of cons truct ion is assum ed to be th e ent ire!)' of"com missioning." ln some instances, this task can be deemed "system commissioning: ' in the sen se of an acceptance test verifying th at so met hin g is funct ion ing as desig ned, but it is no l a substit ut e for the comp lele comm issioning pro Pmcticefor Jhe Co111111issi011ing a11dllrtegmted Testing of cess. NFPA 3, Reco111111e11ded FireProtection mid Life SnfelySystems, is very clear, however, that this is o nly one part of a larger process, and without the approp riate app lication of lhe planning and design phase steps, success at the integrated test ing and occupanc)' stages may be jeopardized. NFPA 3 is a new document, having been issue d for the first time in August of 2012.

CO MMI SSIONIN G TEAM TI1e com missio n ing process is designed to provide a se nse of organization and order to the individuals asked lo carry on l the variou s commissioning tasks. NF PA 3

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provides a list of potential contributors that may be involved in a commissioning team . The list is not intended to require that each commissioning team be composed of the individuals listed, nor is it intended to limit participation in the commissioning process to these indiv idu als, but rather to provide guidance to owners so that they can consider the appropriate p ersonnel ba sed on th eir project needs. TI1e commissioning team may vary in size depending 011 the magnitude of a project, number of systems involved, or contrac tua l agreements in place for a given project. For smaller projects, such as a srnall retail outlet or restaun111t, there may not be a need to have 10 to 12 people involved in the process, as 4 or 5 people can satisfactorily execute the process to a point where all of the goa ls and objectives .u·e met. Meanwhile, a larger project such as a series of buildin gs on a campus or a hospital , with do zens of interconnected systems, may require a team of rnore than 20 people with overlapping roles to complete a project successfully.

Owner TI1e owner of the property plays a crucial role in the commissioning process, because the owner provides the guidelines for the project in the form of the Owner's Project Requirements (QPR). TI1e QPR is intended to be the foundation of the project, as it encompasses the owner 's vision of the project and the general direction for the rest of the commiss ioni ng team. The own er's role in the commissioning process is twofold. TI1e first objective of the owner is to initialize the process by establishing the commissioning team. The second key rol e that the own er plays is to provide review and approval throughout the project. It is the responsibility of th e owner to review and approve any changes to the QPR, cons truction docurnents, c01nm issioning team progress updates, and the final commissioning report. In many instances , the owner does not have the de sire or technical abilities to execute many of these tasks, in which case a designated owner's representative can facilitate the role of the owner. TI1is is typically addressed in a contractua l agreement between the owner and the representative. \,Vhere a rep resentative is used or technical support is brought in to assist the owner, it does not preclude the owner from executing the tasks that the owner has proficiency in, and the role of owner often becomes sha red between multiple entities . Often, the owner will want to stay involved with the administrative aspects of the process but will not be comfortable with the technical review. In these instances, the owner's technical support personnel will provide the owner 's rev iew of project documents and opine on behalf of th e owner.

Commissioning Authority TI1e commissioning authority (CxA) is the individual re sponsible for the execution of the entire total building commissioning process. Most specifically, his or her role is to execute the commissioning schedule and coordinate between the fire com missioning agent and other parties involved in the total building commissioning process. TI1eCxA will be the point of communication between all of the commissioning agents for all of the building systems, not ju st fire pro tection and life safety. 352

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The Fire Co mmi ssioning Agent The fire commissioning agent (FCxA) is the party mos! responsible for the overall execution of the commissioning process for the various fire protection and life safety systems involved. The FCxA provides direction and oversight to the remainder of !he fire protection and life safety commissioning team; therefore, it is critical that the FCxA understands the various systems that arc being considered for the project and has experience in the prop er execution of !he commissioning process. Because of his or her oversight of the process, it is important for the FCxA to ma intain an unbiased point of view and to identify and address all potential conflicts of interest with other comrn..issioning team members prior to kickoff. As Lhe de facto leader of the conunissioning leam, the FCxA is responsible for coordinating and attending all fire protection and life safety comm issioning team meetings. The FCxA will work with the owner to develop the OPR and to identify all commissioning activity responsibilities of the various parties involved. Although many of the tasks that need to be executed in the com missioning proce will fall to other team mem bers, the preparation and execution of the commissioning plan is the sole responsibility of the FCxA. TI1e FCxA also serves as the primary liaison between the commissioning team and the authority having jurisdiction (AHJ). TI1eFCxA is the party responsible for compiling and submittin g to the owner aU fire protection and life safety systems commis sioning document s required by the AHJ.

Installation Contractor(s) Most commissioning teams will include several installation contractors who will be responsible for the individual systems to be included in the project. In addition to installing the individual fire protection and life safety systems in accordance with applicable codes and standards, the iJ1stallation contrnctors must also comply with the responsibilities assigned to them as part of the commissioning plan. This may include attending fire protection and life safety commissioning team meetings, implementing training progra ms, writing test plans, providing submittals to the FCxA, and illustrating that the systems, as installed, function as intended in the OPR and sequence of operations matrix. Attendance at commissioning team meetings is often critical for the installing contrac tors, as this is the opportun ity to interact with other installation contractors Lo discuss the interconnection of fire protection and life safety systems and their cmnponents. Although attendance at these meetings often pulls the contractors away from their on-site responsibilities, it may prove to be a benefit to the construct ion process in the long run, because last-minute testing and installation issues are often avoided.

Manufacturer's Representative For common systems such ns standard sprinkler systems or standpipe systems, the need for a manufacturer's representative on a project may be limited. There are, however, many instances with more technologically advanced systems or interconnections between systems where the manufactur er's representative, active in the commissioning process, can help keep a project on schedule and avoid costly testing failures at the

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fin.ii stnges of the construction phase. When nsed in the process, the mann factnrer's representative is most crilicnl during the component and integrated testing portions of the process. Oftentimes, general contractors and FCxAs will not have int imate details about a product, which can lead to inappropriate seqnencing or connections. Consulting with the manufacturer's representative about the capabilities and limitations of the produ cts can eliminate these issues. The interaction between the manufacturer's representative and the FCxA is especially critical for niche systems that use unique technology or proprietary S)'Stcmcompon ents.

Register d Design Professionals The registered design professional (RDP) is another comm issioning parti cipant, and the number of RDPs involved in a project may vary depending on its size and scope. Some RDPs are capable of providing design services for multiple systems, such as fire pro tection sprinkler and fire alarm system design. Other projects may use a different RDP for each S)'Slemincluded in the project. A qualified RDP should have comprehensive knowledge of the design, installation, operation, and maintenance of all S)'Stems he or she is responsible for. TI1eRDP will also, along with the manufacturer's represenms that they are responsible for tative, provide insight to the FCxA on how the S)•Ste should operate and communicate with other building systems. TI1eRDP is typically responsible for "stamping" or taking ownership of a system design. To that end, the RDP will play a large role in the development of the basis of design (BOD) and will assist with the development of the OPR. These documents rely on conceptual direction from the owner and also technical direction from the design protessionals responsible for the systems. One of the final responsibilities of the RDP is to validate that the systems as installed and tested are consistent with the original intent of the system in the BOD and are consistent with the approved drawings. Oftentimes, where field modifications are required during the integrated testing portion of the constru ction phase, the RDP must submit changes or addend a to the constru ction document s so that the documents on file with the owner and AHJ are consistent with the field conditions . TI1isbecomes critical as new S)'Stems are added, modifications are made, or a recommissioning plan is established for the facility.

Construction Manager or General Contractor The construction manager/general cont ractor typically gets involved during the commissioning as the construction schedule is being developed. TI1econstruction manager will be the liaison between the various subcontractors and the FCxA. Rather than have every individual trade report up to the FCxA, most commissioning plans will use the general contractor as the contact point . Many commissioning pl.ans will incorporate construction milestones into the commissionin g schedule. It is the responsibility of the construction manager to track these milestones and noti f}'the FCxA when they are complete and, in cases where they will not be reached in a timely fashion, show how the etfocts ofmissinga milestone can be minimized.During the installation and construction phases of the commissioning schednle, the construction manager is intended to remedy deficiencies identified by the fire protection and life safety commissioning team. 354

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Once the systems are installed and operational in accordance with the project docu ments, the construction manager will sign off on the project before it is occupied.

Facility Manager or Operations Personnel As stated above, !he commissioning process does not end when the certificate of occupancy is granted; rather the proc ess moves on into the occupancy phas e. TI1ecriti cal role in the proc ess shift s to the facility or operations manager. TI1e facility manager is typically on -site staff responsible for system upke ep and for the ramifications of modifications or ad dition s to the fire protection and life safety scheme of the facility. Facilities management personnel should be knowledgeable and qualified in the opera tion and maintenance of the lire protection an d life safety systems inst alled in their facility. Facilities management personnel who perform or oversee the ongoing system operation and inspection, testing, and maintenance (ITM) should be thoroughly familiar with the required and recommended operation and maintenance tasks. This is not to say thnt the fa ilitie manager is required to perform a!! of the testing and maintenance on the system. Where these task s are conlracted out to an outside agency, the facility manager should have an understandin g of what is required and the frequen C)' with which the outside agency will be involved.

Insurance Representative The insurance representative(s) is typically involved early in the commissioning proce ss to provid e recommendations to the RDP and FCxA for inclusion into the BOD and o ther project documents . TI1e insuran ce representative will provide assurance to the comm issioning team. that the design is consistent with the insurance risk management strategy for the facility. 'fois is why the inclusion of the insurance representative early in the pro cess is important. It is possible for the RDPs to design a system in accor dance with the appl icable design stan dards enforced by the AHJ; however , if the system is not consistent with the insurance agenc)"s requirements, it may require redesign later in the proce ss, which can add cost to the project and cause schedu le delays. The insurance representative will also make periodic site visits during construction to confirm that the systems are being installed in accordance with the BOD and construction drawings. TI1einsurance repres entativ e should also be present to witness system testing as deemed necessary by the FCxA and the contact between the insurance agency and the owner.

Authority Having Jurisdiction A key player in the commi ssio ning process is the AHJ. In many cases, this will be the local building or fire department , or perhaps some combination of the two; however, the term AHJ is not limited to the representatives from the city or town where the proj ect is being constructed. It can also be a government agency, such as a transportation department, or another stakeholder, such as a financial institution. The AHJ is typically responsible for signing off on the various aspects of the commissioning process. The level of involvement of the AHJ in the commissioning process may vary depending on staffing and budgeting; how ever, it is important to include the AHJ in commissioning

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team meetings at their desired frequencr One of the goals of the commissioning pro cess is to enhance communication between the various parties involved in the design and construction process. 111isis extreme!)' important when it comes to communication between the design team and the enforcers on the project. It is also incumbent upon the AHJ to provide the FCxA with all inspection, testing, and performance crite ria required for acceptance and issuance of a certificate of occupancy. l11is information should be included in the project commissioning plan, because it is the final active portion of the construction phase .

The Integrated Testing Agent At the close of the construction phase, the integrated testing agent (lTa) plays the pivotal role of executing the integrated tests for the fire protection systems in the project. l11e role of ITa begins much sooner in the process, however, because much of the !Ta's job involves preparation for the tests . l11e ITa is responsible for planning, scheduling , docu menting, coordinating, and implementing the integrated testing of the fire protection and life safety systems and their associated subsystems. l11e ITa is responsible for confirming that the different systems communicate and function together as intended in the original design; therefore, it is important that the ITa can demonstrate an understanding of the operating components of all systems and subsystem s that are interconnected .

COMMISSIONING

PROCESS

Planning Phase As previously discussed, commissioning does not begin when the integrated system test is needed, but rather it begins before shovels are in the ground . As an administrative process, a large component of commissioning is scheduling and organizing the events that will facilitate a successful project. To complete the project successfully, the goals and objectives must be laid out in the form of the OPR .

Develop the OPR. l11e foundation of the commissioning process is the OPR. The OPR provides the commissioning team with the owner 's intentions for the program of the constructed project. This will include documentation of the size, scope, occupancy classifications, architectural and technological features, interrelationship with other buildings or facilities, integration of systems, and general performance criteria for the project. l11e OPR can be considered the basis from which all de sign, construction, acceptance, and operational decisions are made for the project . As evident from its name, the OPR is primarily developed by a team of personnel representing the owner's interests. It may include financial officers, facilities personnel , trustees, or other stakeholders in the project. l11is is often the place where the architectural perspective for the project is put on paper. Because it is the foundation of the commissioning process , it is imperative that the document be created in the predesign phase, so that the commissioning team members have a reference point as they begin to fulfill their roles and responsibilities in the process.

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1he co ntents of the OPR will vary depending on the size and scope of th e project; howev er, there is so me general information that should be includ ed in th e OPR irrespec tive of size. The OPR shou ld provide a geographical footprint of the proposed proj ect ident ifying its location, height, area, and potential necessary infrastructure such as roa ds, site access, and park ing needs . TI1is inform atio n will provid e th e com m.ission ing tea m with an u nde rstandi ng of the magnitude of the proje ct. Another func tion of the OPR is to provide the com mi ssio nin g team with an und erstandin g of the use of the building, wh ich woul d includ e the occup ancy classification, the anticipated occupan t load, po tential hours of operati on , and also futu re antic ipa ted expans ion of the pro jec t. The OPR also provides the commissioning team with an understanding of the applicabl e codes and sta nd ards for the project, and it provides a reference back to the se documen ts as th e designers work on the various S)'Stems that will be put into the proje ct. Th is is an important link for the co mmissioning team mem bers who are responsible for getting proj ect sign- offs, especially for th e AHJ th at is enforcing th e applicable codes and standa rd s. TI1e OPR is nut solel )' produced to document th e owner's intentions for the proj ec t durin g th e design ph ase, but also to outline many of the user functions of th e facility and how th ey m ay necessita te specific trai ning req uir ements for both facility personnel and respond ing personnel. TI1is may includ e operations and maintenance requirem ents for th e facility, as well as integrated system functions that are critical to day-to -day operations. l he OPR is a dynamic document th at may require updating by the fire protection and life safe ty commissioning team throughout the commissioning proc ess. As th e design and cons truction processes are modified because of budgetary or design con straints, certai n systems may be eliminated from or ad ded to th e original design, wh ich may necessitate a ch ange in the owner's needs . It is important that thes e changes are captu red in the OPR, becau se thi s docu ment is seen as the foundation for th e adm in istrative process that is commissioning.

Commissioning Plan. TI1ecomm issionin g plan is the document in the commissioning process that contains all of the procedures and processes necessary for a successful com miss ion ing process. Not unlik e the OPR, the com missioning plan should be updated by the commi ssion ing team throughout all phases of the commissioning process. Whereas the OPR is the foundation of the commiss ion ing process, the commissioning plan is th e road map that guides th e work of the com mi ssio ni ng team tlu·ough the pro cess. TI1e com mi ssion ing plan .m ay co ntain some of the general project informa tion and scope information found in the OPR; however, the plan will provide more of dir ection for the commi ssio ning process th an project information. The commi ssioning plan will create a go -to so urce for co mmi ssion ing team members, because it will outline th eir roles and responsibilities and the overall conunissioning sche du le. The commissioning sch edu le will identify commi ssionin g tasks and activities, with th eir projected start poillts in th e commiss ioning process and their du rations, and which com missioning team members have ownership of them. W here these tasks require spec ific documentation, meet ings, field activities, or other deliverables, they will be identified in the commissionin g plan. This would also include sequen ce of operation m atrices , testing procedures, and 357

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neces sary training for facilities personnel and emergenq 1 responders. 1he establishment of integrate d test frequ encies during building occupation may also be identified in the commissioning plan. Because the commissioning plan is seen as an integral document in the commissioning proc ess, it is often seen by commissioning team member s as a project reference; therefore, the annex to the commissioning plan will typically contain other project documents such as the OPR, the BOD, submittal reviews, meeti.ng schedu les, specifications, ,md other documents that may be referred to frequently by com mission ing team members. At the end of the construction pha se, the commissioning plan is seen as the final design and const ruction record for the comm issioning team and should be presente d to the owner when the certificate of occupancy is granted.

Design Phase Once the comm issioning plan, OPR. and other administrative and schedu ling- related do cum ents have been finalized , the com mi ssionin g team moves to the design phase. TI1e design phase is where the OPR becomes a living project in design drawings and specifications. TI1ere are severa l do cuments and deliverables that are started during the design phase and continue into the construction phase.

Basis of Design. One of the cri tical documents that is developed during the design pha se is the BOD. TI1eBOD is a narrative report that provides descriptions of fire protection and life safety systems and their components. More importantly, the BOD lays out th e decision -making thought process and logic used by the commissioning team throughout the commissioning process. TI1ereport will describe the performance objective s and performance cri teria of the systems, the applicable codes and standards that require them, and any alternative means and methods for achieving code compliance in regard to these systems. 1his report also addresses the interrelationships between th e systems and the sequence of operation as conceived by the system designers. The BOD, not unlike the OPR and the commissioning plan, will be used as a reference for commissioning team members. It should identify all applicable codes and standards that pertain to the design, plan review, test ing, and ITJ\IItasks required by the A HJ. TI1e references to applicable codes and standards should include all documents that provide requirements for fire protection and life safety systems . TI1ismay include National Fire Protection Association (NFPA) standards, building codes, specialized codes and cri teria (heating, ventilation, and air-conditioning, Occupational Safety and Health Administration, Americans with Disabilitie s Act compliance, etc.), and green building design considerations that impact fire prot ect ion systems. 'l11e logic of the design team shou ld be provided in a section outlining the system objectives and decision s for the project. This sec tion should identif) 1 whether each individual system is required by adopted codes and standards, installed voluntarily, a complete or partial installation, and if it is an addition or modification to an existing system. The report should describe the criteria used by the commissioning team to de termin e performance goals for the facility. "Thismay include building occupant notifica tion, emergency respons e plans, special system features, methods for comp.letion ofITM tasks, and other special considerations taken based on the OPR. Other considerations 358

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for this report would include circumstances in which equ ivalencies (alternative means and methods) were considered for one or more system design methodologies, int erpretations rendered by the A HJ, and any docum entation that may have granted a vari ance or waiver to part of the proje ct design . The BOD also provid es the testing criteria to be used for ind ividual system accep tance testing and for integrated system tests. 1he procedures and methodologies for initial and final integrat ed testing sho uld be outlined in the BOD and doc ument ed for i11clusion in the comm issio nin g plan . T11e BOD is intended to prov ide the comm issioning team's thought processes and decision -ma king processe s in narrative for m. TI1e BOD should describe the criteria used by the commissioning team to determ ine performance objectives for the various fire prote ct ion and life safety systems proposed for the project. Providing this logic is crit ical for facility managers using the systems on a day -to -day basis and for ret rocon11nissio11ing and recom mis sioning teams that may need to modi fy systems or interco nnect new buildin g systems at some point.

Design Method ology. 'Ille project design metho dology should include proje ct documenta tion demon stratin g how the systems operate and communicat e to meet the performance goals and objectives for the facility. Detailed system drawin gs should be provided to demonstrate the specific application of the individu al fire prot ectio n systems used in construction and any spec ific requirements for the interconne ction of systems. T11e methodology should highlight the locations of the fire pro tection systems and procedures for verification of the system performan ce and installation . T11emethodol ogy applies to both active and passive fire protection systems. It should also assign the respons ibilities for [TM tasks related to fire pro tection systems during the design phase.

Construction Phase 'Ille constru ction phase is the phase in which the commission ing plan is physically enacted in the field. TI1ecommi ssioning plan established in the design phase is used to guide the commissioning team through the construction phase. TI1einception of the con struc tion phase is import ant to confir m that the commissioning schedule and other design documents are still valid for the project. 'This wo uld include submi ttals, working plan s, and product specifications. If dwnges need to be made to any of these documents, they should be updated prior to the commencement of construction. After the commission ing team members have determined that the documentatio n is appropriate, they must verify that the materials const ru ct ion and installation processes being implemented are in conformance with the BOD. This will be accomplished via a series of fire protection and life safety commissioning team meetings, field inspections, and progress reports.

Construction Inspections. Co nstruc tion inspections becom e a crit ical part of the com missionin g process, beca use they are the measuring slick for the implementa tion of the commissioning plan. A preconstruction meeting should be h eld betw een the commiss ionin g team and all contractors and subcon tra ctor s who are responsible for the ins tallation of fire protection and life safety systems. It is imperative that all pa rties involved underst an d the schedule, proc edures, and process as outlined in 359

SECTION2: Building Systemsand Fire Protection Systems

the commissioning plan. This initial preconstruction meeting should identify the construction inspection process and schedule. Typically, construction inspections will happen in two parts of the construction process: the rough-in phase and the finish phase. The rough-in phase is inten ded to be an inspection prior to the concealment of system components in walls and ceilings. Once these systems are concealed, inspection becomes very difficult, and any req uired remediation can become extremely cost!}', because it requires the demolition of building assemblies. The rough -in inspection should be used to verify that ins talla tion is proceeding in accordance with the approved shop drawings and commissioning plan. The status of constrnction should be documented and delivered to th e commissionin g team via inspection progress reports . The pro gress reports should identify the progress of construction compared with the commissioning schedule and any deficiencies noted in the field compared with project documentation . All deficien cies noted during the rough-in inspections should be reported to the commissionin g tea m and discussed at com missioning team m eetings so that a remediation plan can be put in place. "D1e number of rough -in inspect ions will vary depending on the size of the project and phasing of construction. For smaller projects, a single rough-in inspection may be appropriate. For larger projects, where phase construction is used, it is conceivable to have numerous rough-in inspections. TI1is is often done on a floor-by-floor basis for high-rise buildings or building -by-building basis for cam pus-type facilities. Once the systems have been concealed, the next inspection phase is the finish phase. TI1e finish phase will typically occur at approximately 90 percent completion of the construction process . TI1e inspe ctions should be conducted to ensure that the final S}'Steminstallation is consistent with the commissioning plan and BOD. Similar to the rough-in inspections, the number and frequency of the inspection s will vary based on the size of the project. Based on the progress reports submitted for the finish phase and the remediation of any noted deficiencies, a final finish phase commissioning progress report should indicate tha t the installation of fire protection and life safety systems is consistent with the basis of design, OPR, and commissioning plan.

Documentation. Because the commissioning process is highly administrative, docu mentation of the activities in the commissioning proc ess is critical. NFPA 3 provides 12 sample forms that can be used to assist in project documentation during the com missioning process. Commissioning teams are encouraged to develop forms and checklists that allow the tracking of progress and project milestones in an efficient manner. A sample commissioning submittal/approval form from the Annex ofNFPA 3 is shown in FIGURE 24-1.This submittal form is used for tra cking purposes to docu ment the transmittal of project information if the com missioning plan and BOD have been followed. Another sample form is a commissioning progress report (FIGURE 24-2). TI1is project progress report can be used by multiple members of the commissioning team and should be submitted to the FCxA prior to commissioning team meetings. T11eprogr ess reports, whether in the design or the construction phase, will allow the FCxA to track project goals and modify the commissioning plan and schedule as nec essary, based on issues being brought forth by team members . TI1e number of forms 360

CHAPTER24 : Commissioning Process for FireProtection Systems

COMMISSIONING SUBMITTA L/ APPROVAL Pr oj ect: _ _ _ _ _ _ _ _ _ _ __

__

_ _ _

Submitt a..lNo .: _ _____

_ _ _

0 New O HesuLmitl al

Fr om (init ial ly): _ _ _ _ ______

'l'o: _ __

_ _ _ _ _

_ _ _ __

_

ID #:

E'qu .iprncnl / !:iys le m name:

Cx Secti on No: _ _ __

Su bmitt a l 'l'ype: 0 Docum entn lio.1.1 (d E'$CTi be):____

0

_ _ _ __

_ _ _ __

Fw1ction9I teat proc«lu r-eforms: _ __

_ _ _ ___

_ _ _ _ __

Compl ete d fun ctiona l test procedur e record or r(lport: __ U

PrefunctionoJ theck1ist: _ _ _ _ _ __

D

S t ar t up a nfl ln it in l ' finding" signs, direction signs, and warning signs, such as "Exit;• "Elevator;' "Stairs;' and "Danger:• inspections for these elements need to account for the fol.lowing: I . Both visual and tactile characters (those that can be perceived using the sense of touch, which includ es Braille) should be used. There may be either one sign with both visual and tactile characters or hvo separa te signs, one with visual and one with tactile characters. 2. Braille shou ld be positioned below the corresponding text. If text is multi lined, Braille shou ld be placed below the entire text. 3. Tactile characters on signs should be located betwe en 48 and 60 in. (122 and 152.4 cm) above the floor to the bottom of the highest tactil e character . 373

SECTION2: Buil ding Systems and Fire Protection Systems

4.

Pictograms shou ld have a field height of al least 6 in. (15.2 cm). Characters and Braille should not be located in the pictogram field (FIGURE25-11 ).

At doors, the signs should be located: 1. 2. 3.

•

I

At a single door localed alongside the latch side. not in At double doors with one c1 c tive lec1f.the pictogram •• sign should be located on the inactive leaf. field At double door wit·h two active leaL5, the sign should be located to the right of the FIGURE 25·11. right-hand door. • If there is no wall space at the latch side of a single door or at the right side of double doors, signs should be located on the nearest adjacent wall. • A clear floor space should exist of at least 18 by 18 in. (45.7 by 45.7 cm) centered on the tnctile chnracters and beyond the arc of any door swing from the closed posltion to the 45-degree open position.

...

Symbols of accessibility and their background should have a nonglare finish. Symbols of accessibility should contrast with their background with either a light symbol on a dark background or a dark S)'!llbol on a light background (FIGURE 25-12). For more detailed information and a complete set of requirements, please see the U.S. Department of Justice 2010 ADA Standnrds and American National Standnrds Institute (ANSI)/Interna tional Code Council (lCC) A 117.l, Accessible n11d Usable Buildingsn11dFncilities.

••••• •••• ••••• (a)

FIGURE25·12a- b.

374

(b)

CHAPTER 25: AccessibilityRequirements

BIBLIOGRAPHY ANSI/ICC Al 17.1, Accessiblen11dUsableB11ildi11gs n11dFacilities.American National Standards Institute, Inc., 25 West 43rd Street, 4th floor, New York,NY. U.S. Department ofJustice, 2010 ADA/ABA Stn11dnrds, September 15, 2010. NFPA Code, Standa rd, and Recommended Practice See the latest version of the NFPA Catalog for availability of the curren t editions of the following document.

NFPA 72®, Nalio11nlFireAlarm {1//dSignalingCode

375

CHAPTER

26 GRASS,BRUSH, AND FORESTFIRE HAZARDS 1\1.ichele Steinberg

A recent National Fire Protection Association (NFPA) study of grass, brush, and forest fires revealed that in the 5-year period from 2004 to 2008, local fire departments in the United States responded to an average of 356,800 such fires annually- nearly 1000 calls a day-with roughl}' 4800 buildings or structures involved each year. Records from the National Jnteragency Fire Center show that the United States loses some 800 to 1000 structures to wildfire in a typical year, with many more destroyed during larger, less frequent conflagrations. Although wildfires may be difficult or sometimes impossible to control, the way Americans design, site, and build homes and businesses can minimize the likelihood of structure loss to these kinds of fires. As an inspector, you can identify opportunities for modifications and improvements to existing structures that can prevent such fires from causing major damage and building loss. This type and level of inspection is a relatively new concept, but recent history and the loss data noted above calls for an inspection program that is able to address the unique hazards associated with th is type of fire. Documentation of wildfire hazards to buildings can greatly assist individual property owners and whole communities in taking action to reduce the likelihood of building loss to wildfires. You need not be a wildfire expert to understand the basic concepts of wildfire risk to buildings. NFPA and its Firewise program offer a wealth of information and training resources for inspectors who wish to increase their kJ10wledgeon this topic.

BUILDINGS LOST TO WILDFIRE: A BRIEFHISTORY Wildfire is a natural phenomenon and a normal, seasonal occurrence in much of North America. Fire is a dynamic process. It obeys the laws of physics and can exist and grow only with fuel, heat, and mrygen.It does not distinguish among fuel sources: dry grass, a free, a shrub, a car, a house, or anything that burns can keep a fire alive. Whereas wildfire can appear to have a random pattern of fuel consumption because of topography

CHAPTER 26:

Grass,Brush,and Forest FireHazards

and weather conditions, especially wind, the ignition and destruction of a home are driven by the characteristics of the home itself and of the area around it within a few hundred feet. \.Yhen homes burn and trees and brush survive, it means the home was more vulnerable to fire than the vegetation. For more than 100 years (until about 1990), the national risk reduction strategy for grass, brush, and forest fires focused on prevention and suppression of all such fires. TI1is approach has resulted in an unintended yet severe consequence. Smaller and fewer fires mean that many areas have become overgrown with vegetation, and as a result, their natural ecologies are out of balance. When paired with just the right terrain and weather conditions, the dense build -up of vegetation results in fires that burn hotter, last longer, and spread faster. 'fl1ese fires become difficult to monitor and control and threaten developed areas more frequently. ·with more and more people living and building in fire-prone areas, we are seeing mounting losses of life and property. Between 1990 and 2000, the United States added more population-32.7 million people - than during any other cen sus period . Counti es in naturally fire-prone areas doubled and tripled in size in just a decade . Fire fighters are very successful in managing more than 95 percent of wildfires, but it is that small percentage of fires that get away that can have dire consequences for communities in their path. Fire fighters cannot instantly extinguish these large blazes and save eveq, structure . Extreme wildfire conditions put dozens or hundreds of structures in danger simultaneously, exposing them to large flames and wind-driven embers from the rnaiJ1 fire. Limited water supply, difficult access for fire trucks, and simple math the number of pieces of apparatus versus the number of homes exposed-mean that fire suppression alone will not allow buildings to survive. Structure losses into the thousands in a single fire event seem to be less shocking with every passing year, as they occur again and again. Unfortunately, research into global climate change suggests that the future of wildfire losses is going to get worse before it gets better . Leading researchers have examined a variety of scenarios for how climate change will affect certain patterns that, in turn, will affect the frequency and magnitude of wildfires well into this century. Research using different future climate scenarios predicts that the amount of biomass, such as forests, scrub, grass, and brush, consumed by wildfire will at least double in the western United States over this century . TI1e need for sound understanding of how to prevent structure losses has never been greater.

UNDERSTANDING WILDFIRE AND STRUCTURE LOSS Wildfire risk is often categorized as though it were driven by location alone, with much effort being put into developing maps to show fire "zones:' Although this mapping can be useful, it belies the reality that structure loss from a wildfire is not contingent on location, but rather on a set of conditions. Fire itself is a process dependent on three elements necessary for ignition. TI1ere must be fuel, a heat source, and oxygen for a fire to ignite and propagate . In a wildfire, the fuel is dry, combustible vegetation including 377

SECTIO N 2: Building Systems and Fire Pro tection Systems

grasses, brush, trees, shrubs, vines, and dead material. Heat comes from many ignition sources, including a lightning st rike or careless disposa l of cigare ttes, but fires will get hotte r with more fuel and plenty of oxygen from the air that surrou nds us. Strong wind s can drive fire up (or down) steep slopes and areas like "saddle s" or "chimn eys;' pushing the fire along to con sume all the fuel in its path. In areas pron e to wildfire, human habitation can become fuel-a stru ctur e with a combustible roof, siding, or decki ng is par ticularly vu lnerable. The co nditi on of a st ruct ure and its surrou ndi ngs makes the stru cture mo re or less likely to ignite in a wildfire. Gra ss, brush, and forest fires become serious threats for stru ctures if they provid e ready fuel for fire. 13uildings sited and built without fire-resistant feature s can ignit e and cause o ther st ructurc s lo burn . How can such a disaster be averte d? Unde rstandi ng how stru ctures ignite is the key to the ans wer, and it goes back to th e simp le/ ire triangle. Wh en one element of the tri ang le- fuel, hea t, or ox,,ge n-is removed, th ere can be no combustion , so the fire goes out. Wh en thinking abou t how to prevent stru cture ignition , we have no control over th e availabil ity of oxygen. Therefore, we mu st look at the fuel and the h eat sides of the triang le. In a wildfire, we are concerned with ignitions o n a hom e's exterior. For wildfire to ignite homes, the same fire tria ngle condit ions app ly. Fuel, in the form of the hom e itself, ou tbuil d ings, and any combustibles immediately around the home , is present. Hea t, which is dose enough to the hou se and any combu stible materi als arou nd the house to ign ite, is p resen t. And oxrgen, naturally, is present. All of these are requ irement s for combustion. ln a real-life scenario, the fuel- heat-o:-..,,gen triangle is complicated by factor s including the type, amount, and arrangement of fuel, the weath er (temperature, hum idity, precipitation , and wind), and the local topography (steep slopes versus flat areas) . With regard to fuel, it is import ant to know that "fine" fuels like grasse s and needles ignit e easily and burn qui ckly. 1l1ese fine fuels can ignite heavier fuels, like tree bran ches and large shrnbs, which take longer to start burning but then burn intense ly. Hotter temp erahJres with dry condition s and strong wind s will intensify and spread fires. The lay of the land will also prov e important in a wildfire. Steep slopes carry fire uphill at an incre ased rate of spread, and such features as can yons act as channels for wind to spr ead fire.

HOW BUILDINGS BURN FROM WILDFIRES:THE STRUCTURE IGNITION ZO NE Even in rm outdo or envi ronme nt, when we talk about fire, we are talking about combust ion. Combust ion occms by tra nsferring energy into a fuel via thermal radiation, co nvection, or conduc tion. Energy is conveyed to the surfac e of a fuel, usually by the rmal radiation or conve ction. 1l1erma l rad iation occurs when heat is transferr ed without the fire touc hing the fuel. Energy is instea d radia ted through space to the surface of the materia l. Convection occ urs when en ergy, usually in the form of a flame, directly touc hes the surface. Now if only the surface were to ignite, a fuel would burn ou t very qu ickly. 'TI1erefore, in ord er to keep a tree trunk, a wall, or any other woody

378

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material burning, energy must somehow be conveyed to the object's interior. Tiiat is where conduction comes in. Once the surfac e of a foe] heats up, the energy is then transferred directly from the exterior of the object into its interior. 'This process causes more of the object's mass to com bust and enables the fuel to burn longer. To put this in the context of wildfire and the exterior of strnctures, consider radiation as heat close enough to a comb ustibl e wall to ignite it. Convection means that flame or fire gases contact an exterio r surface, and conduction means the presence of sufficient heat for a .long eno ugh tim e to cond uct heat from the surface of the wall lo the interior. TI1ese processes often happen simultaneously during a wildfire. Understanding how heat is transf erre d leads us to understand how fire spreads-through a process of combustion. It is important to remember these po ints about wildfire behavior: fire does not spread to homes like an avalanche or flash flood, where a mass eng ulfs objects in its path; fire spreads only to locations along its path that meet its combust ion requirements. TI1is includ es strnctnres. Fire scienc e research on how these processes occur in a wildfire has important implications for how to keep structures from igniting. U.S. Department of Agriculture Forest Service fire scientist Jack Cohen co ined the term "home (or structure) ignition zone" to describe how the structure and everything around it within I 00 to 200 ft (30.5 to 61 m) affect the likeli hood of ignition or survival in a wildfire. Methods to prevent ignition i11this zone include: • Keeping large flames (such as those in a forest fire) away from the structure by incorporating landscape design to bring the flame height to the ground when it gets closer than 100 to 200 ft (30.5 to 61 111)to the structure. • Removing dead vegetation near the stmcture and reducing the volume of live vegetation. • Keeping concentrations of fuel (like firewood) at least 30 ft (9 m) away from the str uctu re. Also imp or tant for preventing structure ignition s are to: • Establis h a "fuel-free zone" that encircles the st ructure and all its attachments, going out at least 3 ft (91 cm). • Reduce the opportunity for firebrands (embers) to collect .in vulnerable places. • Always start with the structure and move out when embarking on mitigation in the struct ure's ignition zone. Observation and media reports of large wildfires may make it hard to believe that individual struc tures can be saved with modifications to the structure as well as changes to th e landscape design that are within 100 ft (30.5 m) of the building. But stud)' after study following devastating fires demonstrates the reality of what happens to structures . Since the 1960s, post -fire investigations have reported totally destroyed structures surrounded by or adjacent to unconsumed vegetation. TI1isindicates that: • High -intensity fire did not "flow" through the area. • Ignition of structures did not occur because ofadjacent high -intensity wild land fire. • The fire did not necessarily spread through the vegetation to ignite structures. 379

SECTION 2: Building Systems and FireProtection Systems

The results of two California case studies showed that for home with noncombustible roofs, house survival depended significantly on the amount of combustible vegetation immediately around the structure. In the 1961 Belair- 13rentwood fire, 95 percent of homes with both a noncombustible roof and between 30 and 60 ft (9 and 18.3 m ) of clearance of vegetation around the home survived. ln Painted Cave, nearly 30 years later, 86 percent of homes with similar characteristics survived. In both cases, the re was no significant intervention to save the homes. Structures survived or were destroyed based on their condi tion. Two factors significantly dominate the potential for ignition: firebrand resistance of a noncombu stible roof and the abilit)1 to keep large flames at least 30 ft (9 m) away. Researcher Jack Cohen created a model to try to make seuse of what the find.ings in case studies and post-fire investigations were impl)'ing regarding structure ignition. Cohen's assumptions in the model included a worst-case scenario large crown fire. His technical assumptions overestimated what would happen even in a worst-case scenario. His calculations focused on the heat radiating from the flame. toward a wood wall and the time it would take for the wood wall to ignite. His calculations indicated that at 131 ft (40 m) from the flame to the wall, it would take more than 10 minutes to ignite the wall. During an actual fire, 10 minutes would be an extraordinarily long time to have flames from a moving wildfire at one location. To try to make the model more realistic, Cohen calculated how close the flame would have to be to a home to ignite the wall durin g a 90-second exposure. He determined that ignition would occur dur ing that time only when the flame was within 100 ft (30 m) of the wall. Later, he was able to conduct experiments to help validate the calculations of his model. He measured heat exposm e and time to ignition on wood walls during contro lled crown fires in the Jnternational Crown Fire Modeling Experiment in Canada's Northwest Territories in 1998. 'Theresearch team constructed wood wall sections measuring 8 by 8 ft (2.4 by 2.4 m) and placed them 33 ft (10 m) from the flaming front of the crown fire. ·n1e wall section charred but did not ignite when only 33 ft ( 10 m) away from the large flames. Case studies, experiments, and models come to the same basic conclusion-the structure and the area around it are key when determi11i.ngigniti.onpotential. TI1escale of the area we should be concerned with is of the order 100 ft (30 m ) or so, not thousands of teet or even a few miles. Although it is true that firebrands can travel from up to a m ile away,the effectiveness of a firebrand is its ability to ignite the house or its immediate surroundi11gs. But what about firebrands? Firebrands or embers that result in ignition can originate from a fire up to a mile nway,dependi ng on the fire intensity and type of fuel burning. A shower of embers will cause multiple ignitions in grass, shru bs, and on vulnerable areas of the home. Firebrands also pose a very serious problem on combustible roofs. A structu re's combustible shingles can potential!)' ignite another structure within 50 ft ( 15 m) of it. Embers can also blow into openings in a structure, gather along fences or under decks, or pile up on other combustible materials around the structure. Without intervention, it is this seemingly "little thing" that time and again has brought str uctures and whole neighborhoods to the ground. Removal of fuels that embers can ignite is a key strategy for preventing stru cture ignition. 380

CHAPTER 26: Grass,Brush,and Forest Fire Hazards

INSPECTING BUILDINGS FOR GRASS, BRUSH,AND FORESTFIREHAZARDS The goal of the inspection is to develop recommended actions for the property owner or resident to reduce or eliminate hazards that you identify . NFPA 1144, Stm1dardfor Reducing Struct11reignition Hazardsjimn Wildlnnd Fire,outlines a consistent approach to such inspections and includes five steps . The steps are ordered in such a way that you will be guided to observe the overall situation of a building relative to the broader landscape, then move to a more detailed examination of the structure itself, and then move back out to the broader landscape. This can help you better to define the struc ture ignition zone for that particular property with a comprehensive list of hazards and to suggest mitigation actions to reduce those hazards.

Step 1: Take an Overview of the Structure's Surroundings T11efirst step is to take into account the physical surroundings of the home . 'TI1isexter nal set of conditions provides a general idea of the property's relative risk from wildfire. In this step, you are looking at the property and its surroundings within 200 to 300 ft (61 to 91 m) for a very broad overview of the area around the structure. Topographic features such as steep slopes, canyons, cliffs, or overhangs should be noted . T11earea's weather is an important factor that will inform residents about what they should be paying attention to during specific seasons. Any nearby structures are important to note, including their relative location to the inspection site and their general condition. The proximity of neighboring properties may provide some clues about how much control the property owner has over his or her structure ignition zone. Nearby fields or forests may be privately or publicly owned and may have an impact on the inspection site's vulnerability. Finally, documenting the structure's location relative to slope is critical for understanding how fire will behave in this area.

Step 2: Inspect from Chimney to Eaves Moving back to the structure itself, begin from the top. Recall that research demonstrates that the condition of the roof will dominate the likelihood of structure survival in a wildfire event. The features you want to consider include roofing materials and assembly, with a Class A roof and assembly providing the greatest protection from embers and flames. Even for a noncombustible roof type, however, the condition of the roofing is critical to observe . The materials and construction of any roof overhangs should be noted, as well as the presence and type of skylights in the roof. Finally, observe the condition of gutters and the presence of any roof litter such as leaves or needles accumulating in roof valleys or gutters. These "little things" can contribute to structure loss in a wildfire. T11egood news is that these hazards can be mitigated quite easily by the property owner. 381

SECTION 2: Building Systems and FireProtection Systems

Step 3: Inspect from Top of Exterior Wall to Foundation Although the roof is the most cr itical structural component for a strncture's wildfire resistance, the areas from the top of the exterior walls to the foundation offer the inspector many opportunities to identify hazard s and recom mend mitigation solutions. This step takes into account all vertical surfaces and openings in the strn ctme. 1l1e inspector must examine the type of material s and construction of the exterior walls and of gutter downspou ts and connectors, windows and oµen ings, and specifica lly the location, size, an d screen ing of any vent openings. Vulnerability of the exterior walls will vary (and can often be mitigated by keeping flammable vegetation and other materials at a distance). Window materials and cond itions are critica l to an understanding of window vulnerability to radiant heat. Finally, vent openings can allow the entry of embers, tho se "little things" that can invad e and burn the home from the inside out. While i nsp cling all sid s of th trncture, you should look at areas next to or und er the st ructure that could be flame sources . Open areas under decks or porches, for example, collect debris and leaves and allow the enh')' of embers. Finally, remember the key phrase about structure hazards in a wildfire: "rf it's attached to the structure, it's part of the structure." Attached accessory structures such as decks, porches, and fences must be inspected with an eye to how they may carry fire to the structur e or allow flames undern eath the structure.

Step 4: Inspect from the Foundation to the Immediate Landscaped Area The area within approximately 30 ti (9 m) from the structure's foundation per.imeter is inspected in this steµ . Recall that this is the minimum distance in modeling and experiments where radia nt heat effects are reduced significantly. You will want to observe the presence, arrangement, and condition of vegetation and other combustibles adjacent to and within 30 ft (9 m) of all sides of the structure. Grasses, shrubs, plants, trees - any vegetation wiJI burn, but the type and condition will dictate to what degree. Dead or dying plants and grasses are dry fuels presenting greater hazards than most live vegetation. Look for clumped or massed vegetation that could provide a major heat so urce. Determi ne whether the arrangement of trees, grasses, and shrubs is creating a "ladd er" effect, where fine fuels on the surface of the ground could carry fire up into the tree crowns. Observe any overhanging limbs or tree branches touch ing or very close to the structure. Observe any other nearb}' fuel packages, which could also include propane tanks, stacked firewood, vehicle parking, or storage of flammable materials. Propane tanks if installed and maintained per code should be of little concern, because most large residential tanks require a 10- to 25-ft (3- to 7.6-m) separation from homes. Small tanks used for vehicles or grills should be stored away from the struc ture.

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CHAPTER 26: Grass, Brush, and Forest Fire Hazards

Step 5: lnsp ct from the Imm ed iate Landscaped Ar a to Extent of Structu re Igniti o n Zo ne Depending on the size of the property under the owner's control, th ere may be some hazards you discover that cannot be simply removed or reduced . Based on wildfire ignition researc h, th e extent of the structure ignit ion zone is 100 to 200 ft (30.5 to 6 1 m) from the pe rimeter of the foundation, Observe the vegetation and other exposures from 30 ft (9 m) and beyond the stru cture perimeter, includ ing topograph ic features such as steep slopes, saddles, or chimn eys, which can help predict the intensity of an approaching fire.

INSP CTION TIQ UETTEAND USE FIN PECTI N FIN INGS Preparing to Cond uct an Inspect ion Depending on the situation, you may be asked to assess a single stru cture or possibly an entire neighborhood. More than likely, you will be inspecting residential property for wildfir e risk. Regardless of the scale, ens ure that you have permission from owners, residents, or local leaders, especially if you plan to enter private property . Comm unity leaders may be able to secure permission from ind ividual residents for you to walk onto their properties for the inspection. Important tools to have with you include a map of local roads (and a topographic map if yon can get on e), a camera , and a not ebook to document your findin gs. Depend ing on the nature of your work, you may want to invite loca l participation from residents and the local fire department , and perhaps even owners of adjacent public land. If you are coordi nating with loca l contacts, have a list of who's who an d a cell phone.

Questions to Ask If you have the oppor tunity, find out as much as you can abou t the area from owners. Import ant informat ion incl udes the size of the community (number of stru ct ures), general character istics of the development, topography and vegetation, con dition of t he roads and infra stru cture, and th e area's worst-case past fire experience or future scenario. The history of fire in the community can help you determin e where and when (seasonally) the next lire might strike an d from what direction it is most likely to app roach. Curre nt co ndi tions will help you determine the likeliho od of ign itio n and how the homes and other resources will be at risk in an extreme wildfire.

Inspec tion Etiquette for Residential Areas You will be tak ing a lot of photos and no tes during the assessme nt, To show respect for owners' privacy, be caref ul not to include hou se numbers or stree t names in

383

SECTION 2: Building Systems and !·ire Protection Systems

your photos. Not every resident will understand the purp ose of the assessment during your visit, and some may be suspicious of your motives or where the information you are gather ing will end up. Behaving as a good neighbor will go a long way toward gaining the comm unity's trust in your assessment of their wildfire risk. You may have a group of residents with you during your visit or you may encounter curious residents during the course of your assessment. Choose your words wisel)'when speaking to them, and help them understand that your judgments about what you observe are focused on how homes llli:l) ' ignite dur ing wildfires. Some of the things you see-for instance, combustible materials around the home- may cause }'Oll concern, but be careful not to characterize this as "junk" or otherwise label residents' habits or behavior. Your assessment, both the words you say and your written assessment, has the potential to influence residents to take positive action to improve their safety. Focus 0 11 facts and positive statements rather than opinions or negative comment s. "Fear appeals" or statements that focus on how dangerous the situation is have proved to be ineffective in motivating residents to act over the long term. Research has shown that these kinds of messages induce apathy rather than action, because people conclude that the situation is so overwhelming that there is nothing they can do.

Documenting and Sharing Inspection Findings In addition to your findings of risk, it is also important to docum ent successful modifications you observe, such as "fuel-free" space immediately around struc tures, use of stone or other noncom bustible materials for walkways and driveways, thinned vegetation, or the presence of noncombustible roofs and other construction features. If appropriate for your situation, a presentation to the owner or group of owners can be very effective in communicating what needs to be done to mitigate the fire risk. TI1e purpo se of this presentation should be to explain in general. nontechnical language the way wildfire behaves around struc tures, the concept of the structure ignition zone, and to clarify how property owners can reduce their wildfire risk. A written document using clear language and numerous photos is also a very effective way to present the results of your inspection to a prop erty owner or group of residents. NFPA'.sFirewise program provides simple checklists and more thorough templates you can use to document your findings and present them to owners. For neighborhood s wishing to take collective action to reduce commu nity-wide risk, NFPA also ofters the Firewise Commu nities/USA® Recognition Program. TI1isseries of simple steps begins with your inspection and leads residents to take action over time to reduce wildfire hazards to people and property.

BIBLIOGRAPHY Cohen, J. D., "Reducing the Wildland Fire Tiueat to Homes: \-\There and How tv1uch?ln: Gonzales-Caban, A., and Omi, P. N., technical coordinators. Proceedi11gs of the Symposi11111 011Fire Eco110111ics, P(n1111i11g mid Policy: Bottom Lines;1999 April 5- 9, San Diego,CA (Gen. Tech. Rep. PSW-GTR-173), US. Department of Agriculture, Forest Service, PacificSouthwest Research Station, Albany, CA, 1999, pp. 189-195. 384

CHAPTER 26: Grass, Brush, and ForestFire Hazards

Cohen,

J.D., "Preventing

Disaster: Hom e Ignit ability in the Wi ld land/Urban Interfa ce;'

Joumal of Forestry,Mnrch 2000. Cohen, J.D., "The Wildland -Urban Int erface Fire Problem: A Consequence of the Fire Exclusion Paradi gm :' Forest History Today, Fall 2008. Foote, E. I. D., Str11 ct11reSurvival i11tire 1990 Sa11taBarbara "Pai11t" Fire:A Retrospecti,,e Study of Urba11Wildla11dbi1e1face Fire Hazard 1Witigatio11 Factors,Mas ter's th esis, vVildland Resourc e Science, Universit) ' of California at Berkeley Grad uat e Division, 1994. s Howard, R. A., Nort h, D. W., Offense nd , F. L., and Smart, C. N ., Decisio11A11alysi

of Fire Protectio11 tmtegyfor tire Sa11taMo11icn Mor111tai11s: A11 l11itialAssess111e11t, Stanford Research Institute, Menlo Park, CA, 1973. Insurance In stit ute for Business and Home Safety, MegaFires:11,e Casefor l'vlitigntio11'flte Witch Creek Wildfire,October2 1-31, 2007, IBHS, Tampa, FL, July 2008 . Note 1635: A Case St11riy ofn Co1111111mity Mara nghide s, A., and i'vlell, W., NIST Tec/111icnl Affected by the Witch arid G11ejitoFires, U.S. Department of Co mm erce, Natio nal In stit ute of Stm1dard and Technology, Ga ith ers burg, J'vlD,April 2009 . Nationa l Fire Protection Associa tion , Assessing WildfireHaznrds in the Home Ig11itio11 Zo11e:!11strn ctor G11id e, NFPA, Quin cy, MA, 2010. Nat ional Fire Protecl'ion Association, Co11ri11cti11g a Comm1111ity Assess111e 11ti11 the Wild/m1d/Urbn11lllte1face [online course]. Availabl e at: www.firewise.org . Accessed December l, 20 11. to the FirewiseCo111111u 11iti es/ Na tional Fire Pro tection Association, UserReference G11ide USA® Recog11itio11 Progm111, NFPA, Quincy, MA, 2009. Perry, M. J.,and Mackun, P. J.,with Baker, J. D., Joyce,C. D., Lollock, L. R., and PearCluwge and Distrib11tio11 1990 to 2000: Ce11s11 s 2000 Brief, U.S. son, L. S., Pop11/atio11 Census Bureau, C2KBR/ 0l -2. Available at http://www.cen sus.gov/ prod/2 00lpub s/ c2k br01 -2.pdf. Accessed December l , 20 11. NFPA Code, Standard, and Recommended Practice See the late st versio n of th e NFPA Cata log for availabi lity of the curre nt editio n of the following document.

Strncture Ignition Hazardsfrom Wi/dla11dFire NFPA 1144, Standard.forRed11cing

385

CHAPTER

27 ROADTUNNELS 1-VilliamG. Connell and NiatthewJ.Klaus, lvISFPE

Th is chapter addresses the importance of ensur ing the operational readiness of fire protect ion and life safety sys terns within road tunnels and descr ibes some of the unique challeng es associate d with the impec tion and testing process in these types of facilities. NFPA 502, Standardfor Road Tunnels, Bridges, and Elevated Highways,addresses the design and planning concepts surrounding fire protection and life safety systems for roadway tunnels and prescribes requirements for operational readi ness and perfor mance testing of these systems. Road tunn el inspectors shou ld also be familiar with the U.S. Depa rtm ent of Transport ation , Federal Highway Administration document entitled Highway and Rail Tm11sitTu1111el Inspection 1Wa mial (2005). This manual provides guida nce on frequency of road tunnel insp ec tions, what to lo ok for when inspecting various road tu nnel fire protec tion and life safety syste ms, and how to doc ument and classify conditional assessme nts. Fro m a fire protection and life safety perspective, road tunnels pres ent signifi cant challen ges that are not seen in typical occupied buildings . .In most buildings, the fuel loads rema in rel ative!}' stat ic; howev er, in road tunnels, new fuel packages are introduced into the tu nnel environ me nt minute by minute. The systems, equip ment, and features necessary to maintain life safety in road tu nne ls are continuously expose d to a sign ificant ly harsh at mosph ere that is common in these facilit ies. Des igning and maintaining eq uipm ent and components criti ca l to life safety and fire protection for such an aggressive environm ent are extreme!}' challenging, and , as a result, these installed S)'Stems will demand a dil igent inspection and operationa l readiness tes t program. Beca use of the profile geometry and generally cons trai ned confi nes within most road tunnels , even a small fire eve nt can creat e a sufficient amount of smoke and excessive a ir temperatures th at can often be fatal when fire protection S}'Stems do n ot function properly. In addi tion to the poten tial for loss of life, fires .in road tun nels can often have significant socioeconomic effects on the regions in which they are lo cated . Many road tunnels provide the ma in source of access into or

CHAPTER27: RoadTunnels

through major cities, and when a fire or other majo r incident occurs, these criti cal tunnels may need to be temporarily closed for repair. 1l1is can cause significant strain on a city or region, particularly if municipal budgets and staff are not in place and prepared to overcome the obstacles presented by the temporary closure of key infrastructure.

GEN RA VERVI W R A FACILITIESAND SYSTEMS

UNN

Road tunnels can be st be classified as enclosed roadwa}' slruc.;turcs used for vehi cular transport. Access to road tunnels is t)'pically limited to an en try and exit port al. Add it ional access points for use by maintenance personnel, emergency responders, and/or for mo tor ist evac uation are common features in many road tunnels. Road lu1111elsare not consi dered places of a sembly or occupied space as typical buildings generally are, because the tunnel users (motorists) are considered a trans ient population. 1l1ere are, howeve r, many similarities between tunnel structures and typical occupied buildings from the perspective of fire protection and life safety. l\fany of the fire protection and life safety systems, both active and passive, that you will find in a building can also be found in a road tunne l. Means of detecting a fire and notifying th e appropriate pe rson nel, as well as rated constrncl ion features and egress, are in tegra l features designed into the tunnel environme nt. Although NFPA 502 does not spec ifically require fixed suppression systems for all roadway tunnels, some tunnels 11sefixed suppression systems, and mo st will use a standpipe system for means of manual su ppression. There are many tunn el design alternatives that can be implem ented depending on the needs of the owner, municipalit)', and/or tran spor tation agency. Several older tun nels operate bidirectional (two -way) traffic flow within a single bore, whereas most new tunnel facilities have been designed with multiple bores, where each bore handles traffic in a single direction. Generally, twin -bore tunnels are designed so that both bores are next to one another at the same elevation. Some newer tunnels now consider stacked arrangements, where one tunnel roadway will sit directly above the other. The structural arrangement of a road tunnel may be selected for one of many reasons, incl11ding financial considerations, geometric/geographic constraints, or transportation planning. Each type of road tunnel arrangement and category provides different fire protection and life safety challenges . NFPA 502 establishes five catego ries of road tunnel s. 1l1e categories are: 1.

2. 3.

4. 5.

Category X-Tnnne l length is less than 300 ft (90 m). Category A- Tunnel length is 300 ft (90 m) or greater. Category B- T11nnel length equals or exceeds 800 ft (240 m) and the maximum distance from any point within the tunnel to a point of safety exceeds 400 ft (120 m). Category C- Tunnel length equals or exceeds I 000 ft (300 m). Category D - Tunnel length equals or exceeds 3280 ft ( 1000 m). 387

SECTION2: Building Systems and Fire Protection Systems

Required fire protection and life safety systems for road tunnels, which require regular maintenance and frequent operational readiness testing, generally consist of all or a combination of the following systems/features dep ending on the NFPA 502 categorization: • • • • • • • • • • • •

Fire alarm Incident detection Traffic monitoring and control devices Emergency communications Emergency ventilation Fixed firefighting system Standpipes Portable extinguishers Tunnel drainage pumps Emerg enC)' lighting Emergency and standby power Emergency egress

INSPECTOR'SREVIEW OF DOCUMENTATION There are many variables that go into the design of a road tunnel, which makes every one of them generally unique from a fire protection and life safety perspective. Not only will the specific fire and life safety systems vary, but also the performance objectives for those systems can vary greatly as well. It is imperative for inspectors to review the original fire protection and life safety system design documentation to understand its intended function and performance objectives. Other important documentation that should be reviewed prior to undertaking inspection of the fire and life safety systems includes previous equipment maintenance records, equipment manufacturers' data (shop drawings, test reports, service bulletins, etc.), operation and maintenance manuals, and original commissioning reports. Road tunnel life safety systems and features are typically performance-based and act holistically to achieve certain results; therefore, it is critical that inspectors understand the specific performance requirements of all systems and features, which may also vary depending on location within the tunnel. It is also important for inspectors to understand that oftentimes these S)'Stems are designed to operate in a specific sequence or combination to achieve the intended performance. fn most cases, it is not sufficient simply to inspect a singular component visually or to conduct individual operational tests that do not sufficiently demonstrate that the overall system is operating appropriately and achieving the intended result. Periodic testing is necessary to confirm that the design objectives for the system can still be met. Oftentimes, these periodic tests are outlined as part of the operations and maintenance programs, but they are sometimes combined with emergency response planning and training exercises. ft is therefore imperative for tunnel inspectors to understand the emergency response plan for the tunnel. Depending on the emergency response procedures, deficiencies 388

CHAPTER 27 : RoadTunnels

may be categorized differently (critical, not critical, etc.), depending on their importance to the overall emergency response p.lan.

POTEN IAL FIRE CONDITIO NS WITHIN R AD TUNNELS The potential fuel sources that can be present with in the roadway tunnel environment are also a major cause for concern. In a typical building environm ent, the maximum heat release rate ofan individual fuel source would typically not exceed 2 or 3 to 4 MW (wooden desk. upholstered armchair, etc.). whereas a road tunnel may contain individual fuel sources in excess of 100 MW Taking into consideration the potent ial for a variety of different fuel sources that may be in transit at 311)' one time, the potential for a catastrophic fire within a road tunnel i significant. The potential fire sizes for roadwa)' fuel packages are identified in TABLE 27-1. Most road tunn els are now designed as limited access tunn els. where the transportation of flammable and combustible liquids and other hazards is either prohibited or operationally controlled. Even with the prohibition of these hazards. limited access tunnels potentially contain hundr eds of megawatts of fuel at any given time. It is important for inspectors and transportation agencies to understand the limitations

Fire Data for Typical Vehicles Peak Fire Heat Release Rates (MW)

Tim e to Peak HRR (min)

Passenger car

5- 10

0-30

Mu ltiple passeng er cars (2- 4 veh icles)

10- 20

13- 55

Bus

20-30

7-10

Heavy goods tr uck

70-200'

Veh icles

Tanker

10- 18

200- 300

Notes: ( 1) TI1edesigner should considerthe rare of lire development (peak heat releaserates may be reachedwithin IO minutes).the number of vehicles that could be involved in rhe fire,and 1he potential for the fire to spreadfrom one vehicle to another. (2)Temperaturesdirectly above the fire can be expected to be as high as 1OOO "C to 1400''( ( I 832"F to 2552°F) . (3) The heat releaserate ma>'be greater than in the table ff more than one vehicle is involved. (4) A design fire curve should be developedin order to satisfy each specific engineeringobjective in the design process(e.g., fire and life safety,structural protection, etc.). 'Maximum registered for open truck. Source;lngason, "DesignFiresin Tunnels; SofeandUeliab!eTunnels, 2006.

389

SECTION 2: Building5)'Sterns and Fire Protection Systellls

of the fuel permitted within the lunnels. Emergency respond ers, such as police and fire depar tments, and oftentimes the transpo rtation agency responsib le for the tunnel facility, will supervise the goods that will be moving in and out of the tunnel environment. Typically, the road tunn el fire and life safety systems are designed taking into account the poten tial hazards or fire scenarios established by the authority having jurisdiction (AHJ). The potential for fire ignition within a roadway tunnel is also quite different than that of a typical occupied building. ·n1emost common causes of ignition in a roadway tunnel are vehicle accidents and overheating vehicles. Oftentimes, a relatively benign incident such as an overheated engine can evolve i11toa large-scale fire emergency because vehicles conta in several types of flammable and combustible liquids including gasoline, diesel fuel, and antifreeze solutions. Add this to the component materials found on vehicles- rubber tires, upholstered interior fabrics, plastics, and fiberglassand a substantial fuel package i created. As noted above, NFPA 502 curren tly categorizes tunnels based on tunnel length. Depending on the length and categorization of the tunnel, different systems may be required for different tunnels. It is impo rtan t that the inspector under sta nd which systems are required to be insta lled based on the tu1111 el category as defined in NFPA 502 , Section 7.2. Shorter tu nnels, such as category X tunnels, which are less than 300 ft (91 111)in length, may require on ly basic traffic contro l systems, whereas a category D tunnel (in excess of 3280 [ 1000 m] or 0.6 mile) requ ires a more complete array of fire protection systems, including means of detection, radio com111unication systems, ventilation, standpipe syste111s,and means for emergency egress. Because many of the requir ements identified in NFPA 502 are defined as conditionally mandatory requirements, the inspectors shou ld familiarize themselves with the original docum entation that identifies those requirements deemed mandatory by the AHJ.

ENVIRO NMENTAL CONDITIONS WITHIN ROAD TUN NELS One of the unique concerns for road tunnel fire and life safety components and equ ipment is their continuous exposure to the ambient environment. Varying air temperature, moisture, precipitation, soot, dust, wind, and the constant potential for collision impact are all variables of a road tunn el environment that are not conducive to fire protection systems and equipment. When fires occur in most buildings, the effects of the outside environment are often negligible because the building envelope provides a layer of protection . fn road tunnel fires, the entry and exit porta ls provide a natur al connection to the outside environment that can have severe eftects on mechanical and electrical equipment required as a part of the fire and life safety systems. Of specific concern are underwater road tunnels and/or cold-weather climates, where a highly corrosive marine atmosphere and/or road salts can rapidly corrode equipment and cause extensive damage to tunnel systems. 390

CHAPTER27: Road Tunnels

OA

UNN L FIREPR AND LI SAFETYSYS MS

N

General Depending on the length of a road tunnel, the fire protection features of the tunnel may vaq•. NFPA 502 categorizes tunnels based on tunnel length and further identifies mandatory and nonmandatory fire protection systems based on tunnel category. TI1e requirements for systems based 011 the tunnel category can be found in Table 7.2 of NFPA 502, which is shown in this chapter as ABLE 27-2. Pire protection in tunnels considers both active and passive fire protection systems, as well as emergency response. Dur ing the plmrn ing and design of a road tunnel, there are many factors that need to be evaluated in the form of an enginee1fog analysis to determine what systems will be necessary abov and beyond the minimum requirements established in NFPA 502 based on the specific hazards of the tunnel. TI1iswould include a review of traffic type and volumes, potential fuels, traffic congestion, tunn el grade, emergency response time, physical dimensions of the tunn el, and tunnel location in relation to emergenC)' responders (e.g., police, fire department, emergency medical services). 1l1e following provides a brief description of some of the more common road tunnel fire protection and life safety systems and features.

Monitoring and Communication

Systems

TI1ereare several means for detecting fires or other vehicle incidents within the tunnel. One of the more prevalent means is via closed circuit television (CCTV). Most moJ

Tunnel Categorie s Fire Protection Systems

NFPA502 Section s

X [See 7 .2 (1 ).]

A [See 7.2 (2).]

B [See 7 .2(3).]

C [See 7.2 (4).)

co S.

D [See 7 .2 (5) .]

0: 5·

co V,

J,

Fire Detection

;;; ~

7.4

CMR

CMR

MR

MR

MR

Manual fire alarm boxes

7.4.1.2

CMR

CMR

MR

MR

MR

ro

CCTVsystems

7.4.1.1

CMR

CMR

CMR

CMR

CMR

a;;;

Automatic fire detectio n systems

7.4.1.4

CMR

CMR

CMR

CMR

CMR

~

7.4.2

CMR

CMR

MR

MR

MR

Detection, identificat ion, and location offire in t unnel

:, "' Q. ::!:)

Firealarm control panel

,:;,

a· :, V,

';;;

;;;

Commun ications Systems Radio

7.5

CMR

CMR

MR

MR

MR

Telephone

7.4.5

CMR

CMR

MR

MR

MR

Stop traffic approaching tunnel portal

7.6.1

MR

MR

MR

MR

MR

Stop traffic from entering tunnel 's direct approaches

7.6.2

MR

MR

MR

NM

NMR

NMR

Traffi c Control

Fire Protection Fire apparatus3

7.7

NMR

NMR

Fire standpipe

7.7

CMR

MR

MR

MR

MR

Water supply

9.2

CMR

MR

MR

MR

MR

Fire depa rtme nt co nnectio ns

9.3

Hose connection

9.4

CMR CMR

MR MR

MR MR

MR MR

MR MR

a

Fire pumpsb

9.5 7.8 7.9

CMR

CMR

CMR

CMR

CMR

CMR

MR

MR

MR

NMR

NMR

NM

NMR

CMR

CMR

CMR

CMR

CMR

MR

Tunnel drainage systemd

7.10 7.11

CMR

CMR

MR

MR

MR

Hydrocarbon detector

7.11.7

CMR

CMR

MR

MR

MR

Emergency egress

7.14.1.1

CMR

CMR

MR

MR

MR

Exit identificat ion

7.14.1,2

CMR

CMR

MR

MR

MR

7.14.2/7.14.4.3

CMR

CMR

MR

MR

MR

7.14.6

CMR

CMR

CMR

MR

MR

General

11.1

CMR

CMR

MR

MR

MR

Emergency pow er

11.4

CM R

CMR

MR

MR

MR

Emergency lig ht ing

11.6

CMR

CMR

MR

MR

MR

17.6.8

CMR

CMR

MR

MR

MR

11.7

CMR

CMR

MR

MR

MR

12.3

MR

MR

MR

MR

MR

Portable fire exting uishers Water-based fire-fight ing systemc Emergency vent ilation systemd

CMR

Means of Egress

Tenable environ ment Emergency exits (includes crosspassageways)e

Electrical Systems

Exit signs Security plan

Emergency Response Plan Emergency responseplan

...,,, '-0 (.;)

MR:Mandatory requirement.CMR:Conditionallymandatoryrequirement. NMR:Nonmandatory requirement. Note:ThepurposeofTable 27.2is to provideassistance in locating roadtunnelfire protectionrequirementscontainedwithin thisstandard. If there isany conflict between the requirements defined in the standard text and thistable,the standard ext shall alwaysgovern. " Not mandatoryto be a unnel\??\;however,they mustbe nearto minimizeresponsetime. b If required,mustfollow Section 9.5. c If installed.mustfollow Section7.9. d Section10.1allows ~ngineeringanalysis to determine requirements. c Emergency exit spac'lngmust be supportedby an egressanalysis.

n

:J:

l> "ti -I m ::c i-.1

~ :IJ

::i: Q. ~ '2 ii,

;:;.

SECTION 2: Building Systernsand Fire ProtectionSystems

them. Thi s may require th e tun ne l operator or authority to h ire a profe ssional fire ala rm maintenance com pany to perform these serv ices. The tu n nel m aint ena nce pla n sho uld establi sh the required freq uency of maintenance and testing of th ese S)'Slems so th at the maintenance compa ny and the AHJ, as well as any needed traffic lan e closures, are scheduled well in advance . Some road tunn els are also eq uipp ed with notification systems to alert mot or ists that the re is an emergency even t occurri ng in the tunnel. This is ofte n ac hieved through the use of horn/strobe systems, public address systems, or var iable-message signage within the tunnel d irecting motorists when and how lo evacua te. In spec tion and tes tin g of l.hese systems shou ld be arran ged as part of th e detec tion system testing.

Emerg ency Ventilation Systems Ventilation systems play a critical role in maintaining a safe environment within road tu n ne ls. It is ex treme ly important for inspection and ma intenance personne l to under stand the purpose of the vent ilat ion system and how the syst em is intended to operate in a part icular road tunn el. An ins pec tion of a tunnel ventilation system must go beyon d simply de term ining the fu nctionality of the mechanical ven tilatio n equ ipme nt ; it must also verify tha t the enti re system is operating as intended by th e de sign. Ventilation is req uired in road tunnels to provide a safe, comfor table environment for motorists. To maintain a safe tunnel environm en t during normal operations, seve ral facto rs mu st be cons ide red . • Safe levels of vehicle -em itted polluta nts such as carbon monoxide (CO) and ox.ides of nitrogen (NOx) must be maint ained. • Visibility must be maintain ed for safe driving . • A tenable environment must be maint ained for motorists escaping a fire emerg ency. Tunnel ventilation methods are categorized as eit her nat ural or mechanical systems . Natural systems re ly on the piston -effect of moving vehicles, external wind, and tempera ture and press ur e differential s between th e portals to generate airflow through the tunnel. Mechanical system s use fans to generate airflow and are generally required for longer tunnel s. There exis t several types of mechanical ventilatio n systems, which are t ypically class ified as longi tudi na l, sem itrans verse, transve rse, or point extract. • Longitudinal systems have air introdu ced to a tunnel or removed from a tunnel at a limit ed numb er of points, such as at: por tals or at ventilation shafts . A popular exa mpl e of this type of system uses ceiling-mounted jet fans to produce the requ ired airflow throu gh the tu n nel. Longitud ina l systems are typically used in tu nn els with unidi rec tional traffic. An example of a longitudinal je t fan system can be found in FIGURE 27-1. • Semitran sverse systems use an air du ct eithe r to supply or to remove air uniformly along the lengt h of a tunnel ventilation zone . A road tunnel m ay be serve d b}' one or m or e ventilation zones.

394

CHAPTER27: Road Tunnels

FIGURE 27-1Longitud inal ventilation using jet fans.

• Trans verse systems use both supply and exh aust air ducts uniforml y to distribute air to and remove air from a tunn el. Typically, air is supplied low near the roadway level to promote the rapid dilution of the vehicle-emitted pollutants. Air is exhaus ted along the hmnel ceiling, which is also advantageous for exhausting hot smoke in the event of a vehicle fire. • Point extract systems typ ically use an air duct with dampers spaced periodically along it. In the event of a fire emergency, the dampers near the fire are opened to enable the exhaust of smoke and heat from near the fire. Each tunnel willuse ventilation modes or methods of operation to meet specific objectives. In the case of a fire emergency, the operational modes of the ventilation system may be different depe nding on the prec ise location of the fire within the tunnel. TI1etunnel ventilation system operational modes (norma l opera tions and emergency operations) should be properly understood by the inspector prior to perform.ing inspection and testing. When inspecting transversely ventilated tunnels, it is also important to verify proper distribution of airflow lo/from the roadwa) ' level. If all the airflow is entering or leavin g the air duct near the ventila tion buildi11g, the ventilation object ives may not be met, and a du ct rebalance could be requi red . When inspecting longitudinally ventilat ed tunnels, it is also important to verify that sufficient air velocity is being generated along the length of the tunnel. Sufficient air velocity is defined as the "critical velocity: • Refer to NFPA 502 for a description of how to determine the critical velocity value for a par ticula r road tunnel.

395

SECTION 2: Building S> •stems and FireProteclion Systems

irefighting Systems Nlost road tunnels includ e two primary methods for fighting fires, includin g standp ipe S)'Stems and port able exting uishers . However, many newer tunn els are also being ou tfitted with water-bas ed fixed firefighting systems. Standp ipe Systems. Standpipe S)'Stems for road tunnels function very simila rly to standpipes found in typ.ical occupied building s. Standpipes are permitted to be wet o r dry based on fire department preference and approval. The system designer must review cri tical variables, such as water fill time, water supply, and climate condit ions, to identify the best aµpro.ich to standpipe design in each tunnel. Heat tra ce is often used as a means for maintaining wet-stand pipes al the appropr iate tempe ratures where freezing is a concern . Where heat trace is used, it is critica l for the inspector to review bo th the hydraulic aspects of the systems and the electrical components of the heat tra ce sy tems to en ure the system functions as intended . The presence of road salts and other chemicals often can serve to expedi te corro sion of water -based fire protection system piping. Visual inspec tions of valves and outle ts for standpipe systems arc important to assure responding person nel that they will have the equ ipment in place to execu te the response plan when they arrive on scene. Portable Fire Extingui shers. Multipurpose portable fire extinguishers are required to be located along the roadway and available for use by motorists . TI1eseext inguishers should be spaced not more than 300 ft (9 1 m) apart and secu red in approved cabinets. It is anticipated that these ext inguishers may be used by motorists responding to an event; therefore, the extinguishers shou ld be limited to a maximum weight of 20 lb (9.1 kg). In many cases, inspectors are unawar e of this requirement or the inten t of the requirement and will spec ify replacement portable extinguisher s in excess of20 lb (9. l kg). 1he maintenanc e of portable extinguishers shou ld be conduc ted in accor dance with NFPA 10, S1n11dnrd for Portable Fire Exli11g11ishers, and the maintenance a nd operations procedures for the individual tunnel. Water -Based Firefighting Systems. Although not spec ifically required by NFPA 502, fixed water-based firefighting systems, including foam systems, automatic spr in kler syste ms, and water spray systems in road tunnels arc becoming more and more prevalent because of the increased level of risk presented by fires in road tunnels, a recent history of serious road hmnel fire incidents, and the grow ing evidence of the effectiveness of the se types of systems in a road tunnel applica tion . Given the increase in new road tunnels being constructed around the world and the grea ter fuel loads of the commodities being tran sported, in some instan ces a fixed water-based firefight ing system is the mo st effective way to mitigate the potential hazards from a tunnel fire. Historical!) ', tunn el operators, designers, and responders have expressed concern regard ing the use and effectiveness of water-based fixed firefighting S)'Slems in road tunn els. These concerns have .largely been alleviated by recent research and test pro grams and by actua l experience. TI1e previous conce rn s included the eflectiveness of automatic sp rin klers on shielded fires inside covered vehicle containers and in engi ne 396

CHAPTER 27: RoadTunnels

compartmen ts, the possible production of superheated steam, a concern that water spraying from the ce.iling of an und erwater tunneJ might induce panic in motorists, and the delamination of the smoke layer reducing the performance of emerg ency ventilation. It is now generally accepted that a water-based fixed firefighting system in a road tunn el is not needed to necessarily extinguish the fire but to prevent a fire in one vehicle from spreading to other vehicles, so that the fire does not grow to a siz:e that could not be ellectively handled by the fire service. Various types of water-based fixed firefighting systems mar be used in road tunnels, including foam-based systems , standard spray spr inkler systems, deluge systems, and water mist systems. Each of these system types carries with it specific compone nt inspection requirements. TI1einspection testing and maintenance of for tlie all water-based fire protection srs tems in tunnels should follow NFPA 25, Stn11dnrd

Inspectio11, Testing,and 1Wainte111mce of Wn/er-BnsedFireProtectio11Systems.

Emergency Egress 'The means of egress from road tunn els may be composed of several different components. A common method for tunnel egress in twin-bore tunnels includes the use of cross-passageways from one tunnel into another and an emergency exit pathway to grade. In some limited -spa n tunnels and older tunn els, where provisions for egress were not cons idered in the design, motorist evac uat ion through the traffic portals is the only option. \•\There required by code and th e environme nt permits, eme rgency exits leading from the tunnel environment to grade are consi dered to be a sate and effective mean s for getting motorists out of a road tunn el in the case of a severe fire emergency. These emergen C)'exits will typically consist offire -rated construction leading from the tunnel to grade. TI1espacing of the exits may vary based on time and capacity requirements ; however , a spaci ng of I 000 ft (300 m) is typica l. TI1ere are several potential issues that can arise with respect to the emergency exits. Often, debris can be accumulated within the tunnel near or in emergency exit enclosures or vestibules. l11is can often imp ede motorists who intend to use an exit during an emergency event. Because of smoke and disorientation, the motorist may not see th e debris and may have difficulty naviga ting it as he or she tries to use the exit. Another potential issue with emergency exits is failure of door hardware, specifica lly closing and latching devices. l11e door assemblies will t)•pically be part of a rated enclosure and therefore carry a fire-protection ratin g. If the door closing device s and latches are not proper!)' maintained, a breach may be created in the rated enclosure that can allow smoking hot gases to fill the enclosure while it is being used by motorists or emergency responders. It is important for inspectors to underst and that although these systems are passive, they play a critical role in the life safety objectives of the tunn el. Another means of evacuating motori sts from a tunnel is the use of cross-passage ways. Cross -passageways are used to connect adjacent tun nel bores. Typically. adjacent tunnel .s will be separated by rated construction. Where this rated construction exists, it may be practical to send motorists from the compromised tunnel into the adjacent

397

SECTION2: Building Systemsand Fire Protection Systems

tunnels, which should not be subjected to any adverse effects from the fire incident. Cross-passageways are also used by emergency responders for quick access to the site of a fire event. Similar to emergency exits, cross-passageway doors are also required to be rated and should be separated not further than 656 ft (200 m) apart. The crosspassageway doors are part of a rated assembly and must prohibit smoke and hot gases from passing into the adjacent tube. It is important that these cross -passageway doors remain closed and latched at all times. This is typically included as a maintenance procedure for tunnel operators to ensure that adjacent bores do not become compro mised from a single incident. iVlany older tunnels or tunnels that were designed prior to modern egress requiremenls rely solely on the tunnel portals a~ a means of escape. In these instan ces, motorists would typically exit their vehicles and walk to the exit portals either on the roadway or on walkways off to the sides of the drive Junes. TI1e emergency response plans for some tunnels will contemplate the use of exit portals for many evacuation sch emes . Because of varying ages and geometrie s of tunnels , it is important for inspec tors to have an understanding of the tunnel evacuation procedures and emergency plans, because they will vary greatly between tunnel designs. Exit signage is required in all tunnels for both cross -passageways and emergency exits per NFPA 502. Oftentimes, these signs can become damaged or fail to remain visible because of general wear and tear. Maintaining the minimum required luminance for the signs and a constant supply of power is important, because most motorists will immediately look for an exit sign once the vehicle is stopped in a fire event. Maintaining egress paths and enclosed exits free and clear of obstructions is critical in tunnels for several reasons. TI1e general lack of comfort by motorists to abandon their vehicles, enter an emergency egress passage, and walk long distances to escape may cause disorientation and delay them in making decisions and using the exit system as it is intended. Another reason why maintaining these systems is critical is that a relatively small cross-sectional area of a tunnel allows smoke and hot gases from a fire event to build up quickly and spread longitudinally along the length of the tunnel. This rapid spread of smoke in the tunnel can significantly cut down the safe egress time for motorists. If components of the egress system, some of which may include pressurized enclosures, are not properly maintained, it may have an adverse impact on a motorist's ability to self-rescue and escape. In addition to the systems briefly described in this chapter, there are other systems critical for fire protection and life safety within road hmnels. Fire alarm, emergency and standby power distribution, emergency lighting, and drainage are all systems that, in concert, provide a protected and safe environment ,vithin these facilities. It is therefore necessary that the maintenance program for any road tunnel includes regular inspection and testing of these various systems.

398

CHAPTER27: Road Tunnels

BIBLIOGRAPHY Highway a11dRail Tm11sil1i11111e/ Inspec//011 Maminl, U.S. Department of Transporta tion, Federal HighwayAdministration, 2005. NFPA Codes, Standards, and Recommended Practices See the latest version of the NFPA Ca talog for availability of current editions of th e following documents.

NFPA I0, St1111dardfor PortableFireExti11guis/rers NFPA 25, Standard f or the l11 speclio11 , Testing, a11dMai11t e11a11c e of H'i1ter-Based Fire Proteclio11Systems NFPA 502, Standardf or Road 1i11111 els, Bridges, a11dEle,•ated Highways

399

ECTION

OCCUPANCIES

3 CHAPTER 28

Assembly Occupancies JosephVersteeg

CHAPTER 29

Educational Occupancies Joseph Versteeg

CHAPTER 30

Daycare Facilit ies JosephVersteeg

CHAPTER 31

Healthcare Facilities Joseph1'vl.Jardin,PE

CHAPTER 32

Ambulatory HealtJ1care Facilities Joseph1vf. Jardi11, PE

CHAPTER 33

Detention and Conectional Occupancies JosephM. Jardi11, PE

CHAPTER 34

Hotels JosephM. Jardi11, PE

CHAPTER 35

Apartment Buildings JosephM. Jardi11, PE

CHAPTER 36

Lodg ing or Rooming Houses

Joseph M. Jardi11, PE CHAPTER 37

Residential Board and Care Occupancies JosephM. Jardin,PE

CHAPTER 38

One - and Two-Family Dwellings JosephM. Jardi11, PE

CHAPTER 39

Mercantile Occupancies Joseph Versteeg

CHAPTER 40

Business Occupancies JosephVersteeg

CHAPTER 41

Industrial Occupancies JosephVersteeg

CHAPTER 42

Storage Occupancies JQs~h Versteeg

CHAPTER 43

Special Structures and High-Rise Buildings JosephVersteeg

CHAPTER

28 ASSEMBLYOCCUPANCIES Joseph Versteeg

Assembly occupancies are defined by NFPA 101®, L((e Safety Code®, as buildings or portions of buildings in which 50 or more persons gather for such purposes as deliberatio n, worship, entertainment, dining, amusement, or to await transport ation (FIGURE 28·1). The charac ter of an assembly occupancy should never be assumed lo rema in constant, and neither should the occupant load. Because the many legal ways in which an assembly occupancy can be used are so d iverse, inspectors should thoroughl y review NFPA JOJ® before beginning an inspection to ensure that they understand the proper requirements for a particular assembly occupancy. Unlike most other occupancies, assembly occupancies e'.1compass a wide range of uses, each of which necessitates different considerations. It is important to note that occupancy of any room or space for assembly pur poses by fewer than 50 persons in a building of another occupa nC)', such as, for example, a 30-person conference room in an office building, is considered incidental to the predominant occupancy. Although subject to the requirements governing the predmninant occupancy, the occupant load of such small assembly uses is to be calculated based on the actual use of the space. For example, a small employee break room containing tables and chairs within a factory is to be calculatt:d based on 15 ft2/person (1.4 m2/ person). lt should also be noted that restaurants or other similar food and drink establishments with an occupant load fewer than 50 persons in a stand -alone building or in a build ing of ano ther occupancy and not incidental to that predominant occupa ncy, such as a 20-seat coffee shop, are classified as a mercantile occupanC)'· As above, the occupant load is calculated on the actual use of the space; that is, 15 ft2/person ( I .4 m2/ person).

OCCUPANCY CHARACTERISTICS Changes of use, or the multi use of assembly occupancies, could result in the application of provisions that normally might not be considered necessary. For example, a building

CHAPTER 28: Assembly Occu pancies

FIGURE 28·1A banquet half.

used as a place of wors hip must meet certa in, bas ic code requirements. Yet this same building also might be used for dining, dancing, or other purpo ses totally foreign to a place of worship, thus tr iggeri ng the need to meet additional code requirements, such as increased width of the main en trance/exit to accomm odate hvo-th irds versus one- half of the occupan t load. Assembly occ upan cies in schools, such as multipurpose rooms, are rented or freely used for purpose s ot her than education and often take on the character of exhibit halls. Such differing stud ent versu s publi c after-hours usage may create differing main exit/entranc e locat ion and requir emen ts. 'The use of available space in hotels. banq uet rooms, shopping malls. and exhibit halls can also be very creative. When inspect ing assem bly occupa ncies, therefore, inspectors must be sure to ascerta in all intended or possible uses. It is also to remember that many assemb ly uses will also occur in an ou tdoor environ ment and that many of the same rules govern .

INSPECTING THE PREMISES As when they inspec t any other type of facility,insp ectors shou ld be seen by the owner of the assembly occupancy as providing a ser vice to him or her by condu cting a fire and life safety insp ection . Inspectors should always meet with the manager or owner of the establishment before begi nning an inspectio n and shou ld encourage him or her to acco mpany them on the inspection .

403

SECTION3: Occupancies

Inspecti ng assembly occupancies is no d ifferent from inspect ing other occupancies. Initially, a general "once-ove r" inspection should be done to spot any immediate con cerns, and the floor area of the building should be de termined th rough measurement. With this information , inspectors can figure out the occupant load of the facility. 'TI1ey should note any exterior violations, such as accumu lations of trash, obstructed fire lanes, or imped iments to exit discharge . They shou ld also point out to the manager or owner any misu se of extension cor ds, sloppy maintenance practices, or other areas of concern so that these can be corrected before the facility is reinspected. Specia l attention should be focused on rear or side doors serving as exits that histori caHy are equ ipped with multiple illegal locks or barricades . \i\Then comp leting an inspection, inspectors should develop and file a sketch or drawing of the facility for future reference. This sketch shou ld show the exterior and interior wall arrangemen ts; th e loca tions of all exit doors; the side yard, stree t, and property line clearances; and any other condit ions of special hazard or conside rati.on of special interest to assembly occupancies . 'TI1esketch should also .identify any portable sliding or folding partitions used to divide rooms, as well as the occupant loads allowed for different room layouts, such as tables and chairs, theater-style seating, danc ing, and so on. TI1issketch is essentia l for future use, not only as a remind er of existi ng conditions but also, more importantly, as an easy reference to determine if an)' changes have occurred since the last inspection. Inspectors sho uld keep a permanent checklist to Indicate the construction of in terior and exterior walls, floor and roof coverings, the flame -spread ratings, the type of heating, the lighting and electrica l systems and their cond itions, the available fire protection devices and systems, and recent approved alterations. This checklist will be useful for future insp ections.

Occupant Load The intended use of the pr emises and the number of ex.its in excess of the minimum number required will influence the max imum allowable occupant load . If the use of the occupancy has changed since the last insp ection, the maximum allowab le occupant load probably has changed, too. If it is a multipurpose space, the inspector should review an)' changes that \\ ou ld affect the variations described in the origina l sketches and sho uld change the sketches accordingly . NFPA 101® contains requirements for calculating the occupant load. If the allowab le load has changed in any way, the inspector sh ould ask the ow ner to provide a new "maximum occupant load" sign and display it as required, provided the means of egress are still acceptab le for the new occupant load. In rare instances, a reduced occupant load may have been approved based on the available egress capacity of the existing egress system. Established occupant loads sho uld be posted promin ently to ens ure that not only the owner but also the manager , opera tor, and occupants are aware of the limitations. Occupa nt loads for multipurpose rooms shou ld be posted for each approved use, such as tables and chairs, theater seat ing, danc ing, and so on. Posting load figures will also help the inspector determine whether the occupancy is overcrowded.

404

CHAPTER 28:

AssemblyOccupancies

In some cases, a method to meter the number of occupants who come in must be put in place by the owner. 111ismay be through a ticket admission policy or a restricted entry policy that keeps account of occupants who arrive and depart.

Means of Egress Exiting i.s the most cri tical of all requireme nts for any assembly occupancy. Whereas the probability of a fire in an assembly occupancy might be low, the potential for loss of life once a fire occurs is extremely high . A fire of any magnitude can easily result in a large number of injuries and deaths. 111erefore, it is essential that assembly oc cupan cies have enougl1 egress capacit}' to accornmoua le the number of people likely to occupy the space and that they be properly located, easily accessible, and well maintained. An NFPA 101® requirement often overlooked when dealing with increased occupant load s is that eg ress apacity hould b e calculated mor e conserva tively when occupants are seated in rows of chairs versus other seating arrangements. The egress capacity is calculated using a factor of 0.22-in. (5.6 -mm) per person when occupants are seated in rows of cha irs versus a factor of 0.2-in. {5.1-mm) per person for other seating arrangements. A life safety evaluation is an added requirement for assembly occupancies having an occupant load in excess of 6000 people. The life safety evaluation is an assessment of what is expected to go on in the assembly occupancy along with a yearly assessment of the following conditions: l.

2. 3. 4. 5. 6. 7. 8. 9. 10.

Nature of events and the participants and attendees. Access and egress movement, including crowd density problems. Medical emergencies. Fire hazards. Permanent and temporary structural systems . Severe weather conditions. Earthquakes. Civil or other disturbances. Hazardous material incidents within and near the facility. Relationships among facility management, event participants, emergenC}' response agencies, and others having a role in the events accommodated in the facility.

Inspectors must ensure that conditions altered since the last inspection have not compromised or blocked egress routes . If any alterations or renovations have been made since the last inspection, the inspector must be sure that travel distances to exits have not been increased beyond the ma xim um allowed. \i\There exit paths merge, the path of travel must be wide enough to accommodate the combined occupant load that can be expected to use the individual paths of travel before they merge. All exit doors must open easil}', with no more than 15 lb (6.8 kg) of force necessary on the panic bar to release the latch. fnsp ec tors must ensure that exit doors are not chained or padlocked closed . Attention should be focu sed on the exterior of exit doors for park ed cars or refus e dumpsters that can prevent the doors from opening fully. 405

SECTION 3 : Occupan cies

Life safety requirements, particularly those relat ing to egress, mu st be maintained at all tim es. Inspec tors must no t allow registra tion booth s, head tables, projection scree ns, ticket booths, turnstiles, revolving doors, guide ropes, and so on to obstruct any means of egress . When loos e cha irs are provided, setti ng up and mainta in ing proper aisles is a par ticularly difficult prob lem. Normally, loose chai rs must be ganged - th at is, connect ed to each other - wh en th e number of chair s exceeds 200. 'The allowable config ura tion of aisles will vary depending on th e type of sea tin g provided - that is, banqu et or conferenc e-type tables, auditorium/theater sea ting arrangements, bleac hers, g rand stands, and so 011. Spaces between and around such seating must be adequate to provide access to aisles. In addition, th e egress routes, as weH as th e exit and directional exit sig ns, should be illuminated in both the normal and emergenC) ' mode .

Interior Finish Another major issu e is th e flame spre ad rating of interior finish material s and the com bu stibilit y/flammability of decora tive mate ria ls, curtain s, drapes, and sim ilar finishings. Int erior finish in stairways should always be Class A. In corridor s and lobbies, it may be Class A or B. In th e genera l assembly area itself, it may be Class A or B; however, .in assem bly occupancies of300 or fewer persons, Class C is permitted. Only ra ted mater ial is aUowed. From a practical sta nd point, flame spread rati ngs are difficult to ascerta in durin g a field inspec tion . If yon are unable to see any markings on the produ cts, you should ask whether the original constrn ction data, any subsequent installation d ata, or manufacturers' test data are available . You should also check th e inspection file for prior accep tance of exis ting materials. Co mbustib le, decora tive materials should be inhe rent ly flame reta rd ant or be capable of be ing treated with a flame- reta rdan t compound. You shou ld ensure that the flame -reta rda nt compound was appro pria te for the material trea ted and done so in accordance with the product's listiJ1g. It might be possible to ob tain a sam pl e of th e decorat ive material from an unob trus ive location-along an inside seam, for exa mple-and test it in a relatively wind -free lo catio n out side th e building by placing the sample in a vertical po sition and setting a flame to the lower edge of the material. If charring does not occur beyond th e flame and no flame or charrin g occurs after the flame has been removed, the product can be assume d to be reaso nably safe. If charring, dripping, or flaming co ntinu es, however, the product is suspect and sho uld be re move d, replaced, or subjected to a standard fire test.

Building Services The inh erent sources of ignition in assembly occupancies also include air -co nditioning , heating, an d refrigeration unit s or systems, electrical wiring, and electrical appliances, as well as conditions that exist in commercial ki tchens. fq •ing and deep-fat cooking constitute the greatest si ngle da nger. Because hood and duct fires are very common, the operating con d ition of the hood and vent extinguishing and exhaust systems shou ld

406

CHAPTER 28: Assembly Occupancies

be inspec ted carefully. Hoods and vents shoul d be exam ined to determine if there has been a buil d-u p of grease. 1hese areas mus t be surveye d and cleaned cont inually, some times da ily. Make sure that the exliaust damper opens when the exhaust fan is operated, approved filters are in pla ce, cooki ng equipment has not been substituted , and th at the fusible link has not been replaced or tampered with . 1he inspecto r should determine the t )'pe of heating system used in the facility and the type of fuel used in the heating system an d shou ld ask the following que stions : • l'v[ust the heating un it be sepa rated from the rest of the buil d ing? • A re the walls, ceiling, and floor of proper construction? • Arc all op en ings, including du ct open ing s, proper!) ' protected? • Arc there any smoke detectors ou the downstrean1 side of filters in the air supply or retur n system? • Is there sufficient com bustion make-up air for the app liance if recently enclosed by walls?

If the heating system fuel is liqu efied petroleum gas (LP gas) . the i1JSpector should find out if the system has shu toff controls that activate automatically if the pilot light goes out. Ts the system locate d where LP gas will pocke t or become trapped in the buil d ing in the even t of a gas leak ? LP gas cylinders sho uld never be stored or used insid e except under vet')' limited conditions. ·where is th e LP gas supply located? If supply tanks are used, the inspector sho uld make sure th ey are properly ins talled, secured, protecte d , and safegua rded against tam pering or accidenta l damag e and that the cyli nd ers are stamped and des.igned for use wit h LP gas. If the fuel is a flammable or combustible liquid , the inspector sho uld determine wheth er the door openin g is diked. On gra vity feed S)'Stems . the insp ec tor should verify that there is an anti- siphon device and should m ake sure there is a fusible shutoff d evice tha t will activate in the event of fire near the heat ing equ ipm ent. When checking the elec trica l wiring and appl iances, the inspec tor should determine wh et her any perman ent installation s h ave been mad e using wiring or equ ipment listed only for temporary use and should ask th e following qu estions: • Are the electric circu its large enough to handle the expec ted load? • Are the non-current -carryi ng me tal parts of p ortable and fixed electrically operated equipment properly grounded? • Have any electr ical extens ion co rds been approved for th eir intended use and are they being used properly?

If the inspector has any doubts about these items, h e or she should have the com munity's elect rica l inspector make the de term ination.

Smoking Smoking is not always prohibited in assemb ly occupan cies, with on e excep tion: smoking is never allowed in theaters or assembly occ upancies simila r to theaters, such as facilities host ing stage shows and concerts. The prohibition or smoking in resta urants is beco min g more popular, and althou gh thi s esse ntially is a health- related issue, no t 407

SECTION 3:

Occupancies

a fire-related issue, the inspector should be on the lookout for unsafe locations, such as stock rooms within the building, where smoking occurs during inclement weather conditions .

SPECIA SAFEGUARDSFOR UNIQUE OCCUPANCIES Stages and Projection Rooms Stages and enclosed platforms present unique hazards associated only with assembly occupancies, and they require special safeguards, such as protection of the proscenium wall, including the proscenium curtain; automatic sprinklers above and below the stage; and automatic venting. Motion picture projection rooms may re quir e special supply and exhaust air, egress, and port openings, all of which must be protected . They also may require room enclosure and proper working space. Projection machines require individual exhaust capabilities, which vary with the type of equipment. Projection rooms, in which cellulose nitrate film is used , must comply with NFPA 40, Standard for the Stomge nnd Handling of Cellulose Nitmte Motion Picture Film.

Exhibitsand Trade Shows Because promoters and exhibitors are often creative in what they want to do and with the materials they want to use, exhibits and trade shows can be challenging to inspect (FIGURE 28·2).TI1einspector should review the products that will be displayed, as well as the exhibits, and closely review special provisions in NFPA IOI® for help with this difficult assignment. Most larger facilities accommodating diverse venues will have approved plans for each venue clearly identifying egress aisles, temporary storage, crowd managers, and so forth. vVhen inspecting exhibits and trade shows, the inspector should make sure to have a plan that shows details of the area, the booth arrangement, the fire protection equipment, and so on . TI1econstruction of exhibit booths should be ofnoncombustible or limited combustible materials, and curtains, drapes , acoustical materials, decorations, and so on should be flame retardant. Multilevel booths and those greater than 300 ft2 (27.9 m2) should be sprinklered when in sprinklered occupancies. Access must be plainly visible, and the travel distance inside a booth to an exit access aisle should not exceed 50 ft (15 m). Cartons and crates should be stored in a room separated from other portions of the building with construction that has a 1-hour fire resistance rating and sprinkler protection. Cooking devices should be limited in number and protected with sprinklers or some other form of extinguishing agent. The inspector may also have to deal with motor vehicles displayed in this type of occupancy. 1he electrical system on vehicles should be disconnected to reduce ignition sources, and fuel tanks should be sealed. Fueling and defueling should not be 408

CHAPTER 28 : Assembly Occup ancies

FIGURE 28·2Trade show.

allowed insid e the structure . Additional concerns regardi ng sprinkler coverage arise when structures or buildings are constructed within the facility during events like a home show.

Special Amusement Buildings Special amusement buildings present yet another life safety problem because they generally entertain customers by intentionally confusing them. Nonetheless, the means of egress must be plainly visible and lighted during an emergency. Under certain condi tions, smoke detection systems ma)' be necessary. NFPA 101® requires that every special amusement building be protected with automatic sprinklers. Movable or portable specia l amusement buildings must also be protec ted, and the water supply must come from sources approved by the au thority having jurisdiction. NFPA JOJ®con tains specific criter ia within the means of egress port ion of the assembly occupancy chapters for calculating the minimum width of aisle accessways and aisles serving seat ing arranged in rows, as well as for seating at tables. In addition, specialized seating arrangemen ts such as grandstands and folding and telescopic seating are contained within the specia l provisions portion of the assembly chapters. TI1e requirem en ts governing grandstands, in add ition to establish ing minimum spacing dimensions to ensure safe egress, contain structura l requirements for portable grandstands to safeguard against collapse; size limitations on wooden grandstands in the event of fire; and safeguards against fire for the area immediately beneath all types of grandstands. 409

SECTION 3: Occupanc ies

EMPORARYCOO KING AND OPEN FLAMES Inaddi tion to the sources of heat and open llame previou ly discussed, restaurant owners often use table candles to enhance the atmosphere. This practice should be discouraged. When it is permitted, however, the candles should be placed in stable containers or holders of noncombu stible construction that are designed not to tip over easily.1he inspector should test one of the typical candleholders to ensure that the flame does not come in contact with other combustible materials if it does tip over. Obviously, the test . hould he performed outsid . Table carts with open llames used as food wnrmers or for actual cooking are another potential source of ignition. 111many cases, food on these tables is saturated with alcohol, which is then ignited. This activil)' is generally conducted very close to the restaurant patrons. There is no established means of protection again t the obvious hazards of this practice, except prohibition . Both NFPA 101® and Nf PA 58, Liq11efied Petroleu111 Gas Code,limit the indoor use of portable butane-fueled appliances in restaurant s and .in attended commercial food catering operations to situations where the appliance is fueled by not more than two I 0-oz (0.28-kg) LP gas cap.icily, nonrefillable butane containers that have a water capacity not exceeding 1.08 lb (0.4 kg) per container. Storage of cylinders is also limited to 24 contai ners, with an addit ional 24 permitted where protected by a 2-hour fireresistance rated barrie r. 1he practice of bringing large propane or butane containers indoors is common in restaurants and presents an extreme life safety hazard. In places of worship, the congregation occasional!)• holds lighted candles and sometimes marches in procession with them. Whereas limited use of candles by designated officials can be permitted for religious purposes, the general assembly participants should not be allowed to hold any open flame devices. Pyrotechnics and llame effects traditionally have been used on the stages and platforms of assembly occupancies, particularly duri ng magic acts or shows. With the advent of discotheques and rock concerts, however, there has been a dramatic increase in the use of features. 111is practice can create extremely hazardous conditions depending on the type, volume, setting, and control exercised when they are used. See NFPA 160, Standardfor /he Use of Flame Effects Before 50 ft (>15 m)c

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NS

AS

"'O

V

NS

::, "' r,

AS

(2) Closable from the inside (3) Provided with smoke control NS:Not protected by automatic sprinklers. AS: Protectedby automatic sprinklers. NR: No requirement. SR:Smoke resistant.FR: Minimum 1-hour fire-resistance rating. Notes: (1) Doors in openings in partitions required to be fire rated (FR)in accordancewith Table23.3.8, in other than required enclosuresof exits or hazardousareas, are requiredto be substantial doors of construction that resistsfire for a minimum of 20 minutes.Vision panels with wired glassor glass with not lessthan 45-minute fire-rated glazing are permitted. Latches and door closersare not required on cell doors. (2) Doorsin openings in partitions required to be smoke resistant (SR) in accordance with Table 23.3.8are required to be substantial doors of construction that resists the passage of smoke.Latchesand door closers are not requiredon cell doors. (3) Under UseCondition II.UseCondition Ill. or UseCondition IV, a spacesubdivided by open construction ;any combination of grating doors and grating walls or solid walls) is permitted to be considered one room if housing not more than 16 persons.The perimeter walls of such space are required to be of smoke-resistant construction. Smokedetection is required to be provided in such space.Under UseCondition IV, common walls between sleeping areas within the spaceare required to be smoke resistant,and grating doors and fronts are permitted to be used. Under UseCondition II and UseCondition Ill, open dorm·1tories are permitted to house more than 16 persons,as permitted by other sectionsof this chapter. (4)Where barriersare requiredto be smoke resistant (SR),the provisions of Sections 8.4 and 8.5 do not apply. aMight be no requirement (NR)where one of the following is provided: (1)Approved automatic smoke detection systeminstalled in all corridors and common spaces. (2) Multitiered cell blocks meeting the requirementsof 23.3.1.3. bMight be no requirement (NR)in multitiered,open cell blocks meeting the requirements of 23.3.1.3. CTrave l distance through the common spaceto the exit accesscorridor. d"Totalopenings in solid room face'i nclude all openings (e.g.,undercuts,food passes,grilles).the total of which is notto exceed 0.85ft 2 (0.08 m2). All openings are required to be 36 in. (915 mm) or lessabove the floor.

~-

CHAPTER 33: Detention and Correctional Occupan cies

Lockups Lockups are considered by NFPA 101® to include spaces in nondetention and correctional occupancies used for the periodic detention of persons. Customs facilities at airports and police precinct holding areas are examples. Lockups in occupancies other than detentio n and correctional occupa ncies that house more tha n 50 people or provide for 24-hour detention must comply with the general requirements of detention and correctional occupancy provisions of NFPA 101®. However, those detaining 50 or fewer people for less than 24 hours are exempt from the general occupancy chapter provisions of NFPA JOJ®. vVhen lockups are .located in these other occupancies, the requirements of the pr dominant occupancy of the building mu t be met along with the specific lockup rules found in NFPA 101. Additionally, the fire department must be notified of the presence of the lockup. To ensure the safety of the detainees, the following additional safeguards should be in place: • Ensure lliat stalTcan affect the release of those in lockup within 2 minutes. or

• If the goal of 2-minute release is not met, ensure the lockup is equipped with a smoke detection system and the lockup is protected by a fire alarm system. Also, door hardware within the lockup's means of egress must comply with American Society for Testing and Materials (ASTM) 1577, Stnndnrd Testlvfethodsfor Detention Locksfor SwingingDoors.

BIBLIOGRAPHY ASTM 1577, S/a,1dnrd Test Methods for Detention Locks for Swinging Doors, 2005, ASTM International, 100 Barr Harbor Drive, P.O. Box C700, \•Vest Conshohocken, PA 19428-2959 . www.nst111.01g NFPACodes,Standards,and RecommendedPractices See the latest version of the NFPA Catalog for availability of current editions of the following docum ents.

NFPA 82, Stn11dnrd011l11ci11emtors nnd Wnste n11dLinen Hn11tili11g Systems nnd Equipment N FPA90A, Stnndnrdfor tire Jnstallntio11 of Air-Co11ditio11i11g n11d\le11tilnti11 g Systems NFPA 101®, Life Snfety Code® NFPA 220, Standard 011TypesofB11ildi11g Co11structio11

457

CHAPTER

34 HOTELS JosephNI. Jardin, PE

The term liote/ is not specifically reserved for the modern fire-re sistant high-rise building. Indeed , it may apply to any motel, inn, or club that provides sleepi ng accommodations for more than 16 people . As a result, hotels generally present a wide range oflife-safety and fire protection problems. Inspecting hotels poses a special challenge because, in addition to providing sleeping accommodations for transient guests, hotels may house facilities such as meeting rooms, ballrooms, theatrical stages, kitchens, restaurants , storage rooms , maintenance shops, garages, offices, and re tail shops, each of which may be classified as a different type of occupancy. For example, guest rooms are classified as residential occupancies, whereas ballrooms, theaters, and restaurants are assembly occupancies . Offices are business occupancies, parking garages and storage areas are storage occupancies, maintenance shops are industrial occupanci es, and retail shops are mercantile occupancies. If these different occupancies are separated from one another and each has its own means of egress, they can be considered separate occupancies according to NFPA 101®, L(/e Safety Code®.If they share th e same means of egress, the building is considered a mixed, multiple occupancy, and egress and fire protection requirements should comply with the most restrictive requirements of the occupancies involved.

INSPECTION OBSERVATIONS Before inspecting a hotel, you should become familiar with NFPA 101®, which contains requirements for means of egress and fire protection for new and existing hotels. NFPA 101® also provides requirements for operating features, such as fire drills and employee training.

Means of Egress Occupants should be able to evacuate quick!)' and safely from a hotel to reduce the potential for loss of life. TI1eguest room corridors should have a minimum clear width

CHAPTER34: Hotels

of 44 in. (111.8 cm) and be free of obstructions. Exit signs should be readily visible and should clearly identify the path of travel to each exit. NFPA 101® requires emergency lighting in atl)' hotel with more than 25 rooms. Occupants on each floor shoul d have access to at least two separate ex.its. In newer buildings, the se two exits are required to serve each floor. In general, you sho uld verify that at least two of the exits are considered remote in accordance with Chapte r 7 of NFPA 101® (i.e., a single fire will not block access to both exits). For recently constructed buildings, you shou ld verify that the exits are remote using the ½ diagonal d istance convention (½diagonal if sprinklered) and shou ld ensure that corridor com mon paths of travel and dead ends are less than 35 ft ( 10.7 m) long (50 ft ( I 5 m) in sprinkle red buildings]. lf guest rooms or suites exceed 2000 ft2 (185.8 m 2), they are required to h ave two remotely situated exit access doors. You shou ld co nfirm the integrity of the exit enclosur es serving each floor. The construction of the enclos ing walls should be intact and possess the appropriate fire-resistance rating (a I -hour rating for all sprinklered non -high -rise buildings and nonsprinkle red buildings where exit stairs connect three or fewer stor ies, and a 2-hour rating for all non spri nklered building s wh ere exit enclosures connect three or more stories). The door s should function properly; they should swing open without the app lication of extreme force and should fully close and latch. You should verify the presence of a fire door lab el indicating the required fire protection rating (e.g., 1 hour for I-hou r enclosures and I½ hour s for 2-hour enclosures). Stair landing s as well as the area beneath the lowest flight should be free of storage or any other use other than egress. An inspector needs to consider if the hotel has a sole evacuation route passing through another occupancy. TI1is arrangement is permitted only und er the following conditions: • The building is fully sprinklered, and the sole means of egress does not pass through a high-hazard contents area . or • The sole evacuation route is separated from the other occupancy by fire barriers with at least 1-hour fire-resistance ratings, and the sole means of egress does not pass through a high -hazard contents area. TI1e exit discharge area should be examined to ensure that the egress is free of impediments. Look for parked vehicles, trash containers, shrubbeq 1, or fencing that might obstruct access to the public way. All fire escape stairs (permitted on certain exist ing hotels only) or ou tside stairs, if provided, should be inspected from top to bottom. The fire escape stair must be attached securely to the outside of the building, and all handrails and guardrails should be secure. Counterweights on fire escapes should be free to swing when necessary to lower the stairs. TI1egeneral condition of th e structure and the quality of maintenance shou ld be noted . There should be no accumu lated trash beneath tbe outside stairways and fire escape stairs.

459

SECTION3: Occupancies

Means of Escap The area within th e guest room or suite is required to comply with the means of escape provisions of NFPA 101®, Chapter 24, One- and 1\vo-Family Dwellings. Means of egress provision s apply to area s outside the guest room or suite. You should revie w the means of escape provisions found in Chapter 38 of this book.

Interior Top Floors. Int e rior inspection ca n start at the top or bottom of the hotel, but beginning at the roof will provide a bird's -eye view of the building. Restaurants and meeting rooms may be located on the top floors of hotel s, particularly in high -rise hotels. These are assem bly occupa ncies and should comply with the requir ements ofNFPA JOI® for new or existing assembly occupancies. The occupant load of the se occupancies sho uld not exceed the available egre ss capacity. Keep in mind that the occupant load may have changed as the result of renovations. Guest Room Floors. Generally, the guest room floors cons ist of guest rooms opening into a corri dor. Protecting these corridors from smoke and fire is critical. Corr idor s should be properly fire-resistance rated and complemented by doors with appropriate fire protect ion ratings. 1'vlost new hotels will be sp rinklered; th erefore the walls should po ssess a ½ -hour rating. Nonsprinklered new hotels require 1-hour fireresistance rated walls. Corridors in nonsp rink lered existing buildings are required to have ½-hour fire-res istan ce rated walls. If the existing bui lding is sprinklered, then the walls must si mply be smoke resisting. Corridor doors must be self-closing and latching. Generally, the doors should have a 20-minute fire protection rating; corri dor doors in sprinklered existing bui ldin gs, however, must simply resist the passage of smo ke. If a fire occurs in a guest room and the guest evac uates the room, the guest room door must close and latch to protect the corridor from heat and smoke at least for the tim e it takes the guests to evacuat e. Tirns, it is cri tical that the doors' self-closers work properly. Transoms over the doors in co rridor walls shou ld be permanently fixed in the clo sed position. Transfer grilles and louvers in corridor walls are permitt ed on ly if automatic sprinklers are installed or if smoke detectors in the corridors are arranged to shut down the fans that draw air into the co rridor from the guest rooms. Transfer grilles must be locat ed in the lower third of the corr idor wal l (a summary of corridor wall features is provided in FIGURE 34·1and FIGURE 34-2). You should exam ine a few guest rooms to ensure that their door s are self-closing and that the doors close completely and latch . Each room should be equipped with a work ing smoke alarm, and fire safet)' information should be posted in each room. The guest room smoke alarm is intended to set off an alarm in the room to alert th e occupant. It is not intended to sou nd the alarm throughout the building. Because of the h igh incidence of nu isance alarms, these smoke alarms are not requir ed to be connected to the building fire alarm system . 460

CHAPTER 34: Hotels

.- -

-+1-hour (½-hour if sprinklered)

Self-closing device

,.___ __

No trans fer grilles or louvers

No unprotected open ings

0

FIGURE 34·1Corridorwall features.Source : Exhibit 28. 9fromLifeSof etyCodeHoodboo k.

-;==-=--,,.._- ---

-

Transom fixed closed

, r---1----

Special provisions for transfer grille

\

2 storie s or >50 units t

Annunciator panel

Annunc iator panel

Annunciato r panel

Smokeproof enclosures

Door fire resistance

Interior finish

Within Living Unit (Apartment) Escapewindows, per Secti on 24.2 (See37.2.1.)

Alarm System Annunciator panel

R: Required(seeCodefor derailsand exemprions).NR:No requirements. IOI®.LifeSafery(ode®, 2012,Tab le A.31.1. +Number of stories in height. Source:NfPA c:o

C

25: s·

~

SECTION3: Occupanc ies

INSPECTION OBSERVATIONS General Observations The new inspection actually starts as the inspector approaches the building: 1.

Is the distance to the nearest fire hydrant acceptable?

2. 3.

ls the hydrant on a public main or is it a private water system?

If it is a private hydrant, has it been tested to ensure the proper flow and pressure? stallatio11of Private 4. Was it installed according lo NPPA 24, Sta11dardfor the !11 Fire Sen•ice Mains a11rlTheir Appurtc1u111ccs? 5. V{hat is the water supply? (iviany garden- type apartments have private water supplies.) 6. Are there obstructions to fire hydrants such as trees, shrubs, trash collectors, or new co11slruclion? 7. Is access to the building blocked by signs, marquees, or overhangs that could inhibit rescues? Older bu ildings could have old fire escape stairs in need of replacement or repair. They shou ld be closely examined to ensure they are strncturall y stable, properly installed, and sufficiently maintained . Furt her ensure that the fire escape stairs are not obstructed by plants, cloth eslines, air-conditi oners, or any othe r objects that might block use by fleeing occupant s or respond ing fire fighters. Old fire escape stairs should not be confused with the safer, more subs tantial outs.ide exit stairs that could have been added to remedy exit deficiencies where installing new interior sta irs was nol practical. NFPA 101® gives requirement s for acceptable construction of outside stairs. You should make sure that materials posing a fire hazard arc not stored on or under the outs ide sta irs. At the beginning of the inspection, check that the use of the building has not changed or that anoth er occupancy use has nol been added. If the building shares the premises with another \ }'PC of occupancy, such as stores or offices, NFPA 101® considers the building as a multiple occupancy building. If it is a mixed-multiple occupancy building, the most restrictive life-safety requirements of the occupancies involved must be applied throughou t the bui.lding, because separate safeguards are impractical. An apartme nt building may be located above another occupancy only if it is either separated from that other occupanq' or the nonresid ential occupancy is properly protected. For example, if there is a dru gstore (mercant ile occupancy) on the premises that was not the re at the last inspection, either separation between the store and the apartments rnust be provided by means of construc tion having a fire-resistance rating of at least I hour or automatic sprinkler protection must be provided for the store area. An inspector needs to consider if the apartment occupancy has a sole evacuation route passing through another occupancy. TI1is arrangement is permitted only under the following cond itions: • The building is fully sprinklered, and the sole means of egress does not pass through a high-hazard contents area.

470

CHAPTER35: Apartmen t Buildings

or • The sole evacuation route is separated from the other occupancy by fire barriers with at least 1-hour fire-resistance ratings, and the sole means of egress does not pass through a high-hazard contents area.

Occupant Load Although the occupant load is not required to be posted in a conspicuous place in apartment buildings, it is neverthelessan important consideration in the number of exits. The occupancy load for apartment buildings is one person for every 200 ft2 (18.6 rn2) or gross floor area. Some apartments coulJ have dorrnitory-lypt: slt:eping arrangements, such as several or many bunk beds in apartmen ts occupied b)' students, which would appear to increase the occupant load well beyond the 200 ft2 (18.6 m2) per person criterion. If the occupancy is found to exceed this limit, adequacy of the egress apacity hould be assessed.

Exits You should check to make sure that all exit doors operate properly and that the means of egress are not blocked in any manner and are not hazardous in any other way.One of the greatest problems in existing apartment buiJdingsis that through age or lack of maintenance, those life-safety features originally constructed into the building have deteriorated to the point where they no longer function. In many apartment buildings, it is quite common for tenants to put wedges under the doors that lead into stairwells to keep the doors open. Unapproved devices must not be allowed to hold the doors open. Examine the latching devices on all fire-rated doors, and check that self-closing devicesand latches function properly and completely close the door. Ensure each fire door is intact with listed hardware and either wired glass or rated glazing if vision panels are discovered. Very often, doors are damaged by misuse or abuse and then are "fi..x:ed" using subpar materials. TI1e accumulation of household goods and trash in corridors and stairwells is a common problem. Trash should be removed immediately so that egress out of the building can be safe and quick if a fire should occur. Many apartment buildings provide the tenants with storage areas, but even when such areas are not provided, some areas seem to evolve into storage spaces. TI1eseareas should be closelyinspected. Almost anything, including outboard motors, flammableand combustible liquids, old tires, mattresses,and all kinds of furniture, will be found. TI1ese materials ma)' have accumulated over many years and might cause the fuel load to exceed that which the building was designed to handle, Many times, these spaces communicate with the means of egress or with vertical plumbing stacks, and there is almost always a lack of proper separation from the floor above. TI1ecode requires that these spaces be protected by 1-hour construction or by an automatic sprinkler S)'Stem. In extreme cases, both may be necessary.

Dwelling Units Most of the time, you will not be able to enter the iJ1dividualdwelling units. But you should inspect public areas, such as corridors, stairs, storage areas, utility areas, the 471

SECTION 3: Occupancies

building exterior, and exit doors. If central air-conditioning is a part of the building, check carefully for th e accumulation of stored materials in the fan rooms. If renovations have been made, check to ensure that the distance to exits has not been violated. NFPA 101® requires that each unit in an apartment building be equipped with single station or multiple- station smoke alarms that are continuously powered by the house electrical service; they may not be battery operated , except for Option 2 and Option 4 buildings, which are permitted to possess battery -powered smoke alarm s. TI1is requirement is in addition to any sprinkler system or other det ection system install ed in the building . Installation of single- station and multiple -station smoke alarms must comply with N FPA 72®, National Fire Alarm and Signaling Code. NFPA 72® requires that , in addition to a smo ke alarm located outside of each sleeping area , a smoke alarm mus t be installed on each story. If possible, arrange with the building manager to look at the smoke alarms in a vacant apartment or randomly sample apartments, which should be representative of smoke alarm installations throughout the building. Also ask to witness a test of the rep resentative smoke alarm( s). TI1is will at least show whether the manager know s how to condu ct a test following the manufacturer's instructions . If the manager is not able to do this, the information is probably not being passed on to the tenants. You should also check individual apartments to be sure the entrance doors are self-closing . NFPA 101® require s that doors between living units and corridors be selfclosing . A fire occurring in an apartment could easily generate sufficient smoke, heat, and toxi c gases to create untenable condition s in th e corridor if air transfer grills were permitted. NFPA 101®, therefore, does not permit transfer grills in the doors or walls that make up the corridor wall assembly (see the summary of corridor wall features in FIGURE 35·3.

Self-closing _ _,,., ~ .,_ device

----

I

Transfer grilles prohibited

\

,?

½-hour

-

-

-

- No unprolected openings

0

Option 1 or Op lion 2: 20-minute or 1~4in. ( 44 mm) solid Option 3 or Option 4: nonrated, resists passage of smoke

FIGURE 35·3Corridor wall protection in existing apartment building. Source : E: uill?/

0

E.

N~

/ /

_J__

.S

"~'L,

E

E E

0

~ ~ In new constrnction, approved, single-station, VI ~ building-powered smoke alarms must be Floor installed in every sleeping room, outside of each separate sleeping area in the vicinity of 2'34.2 111 , the sleeping rooms, and on each level of the (2'870mm) dwelling. Where hvo or more smoke alarms are required, they must be arranged such that ,£ E ?:5.7112 the operation of an)' smoke alarm will cause all ~ ~ (2'0.53 m2) other smoke alarms in the dwelling to sound an alarm. Approved, building-powered smoke detection systems that provide for occupant E .£ E notification are also acceptable in new con0 (inside looking oul) ~ ~ VI struction. Reter to Chapter 15 in this book, as ~ well as NFPA 72®, Nntionnl Fire Alnrm n11d Floo r Sig11nli11g Code,for additional information. Battery-powered smoke alarms are permitted in existing one- and two-family dwellFIGURE 38·1Escape window minimum ings and must be installed in ever)' sleeping op ening dim ensions. (inside looking ou l)

AIE

□

~~

498

CHAPTER 38: One-and Two-FamilyDwellings

FIGURE 38-2Combination COand smokealarm.

room , outside of each separate sleeping area in the vicinilr of the sleeping rooms, and on each level of th e dwelling. New one- and two -family dwelling s that co ntain fuel-burn ing appliances or attached garages are req uired to have carbon monoxide dete c tors installed in the imm ed iate vici nity of eac h sleeping area and on each level that may be occupied (including basements) (FIGURE 38-2). One - and two-family dwellings are required to be protected throughout by a sprinkler system in accordance with NFPA 13D,

Standard for the J11stallatio11 of Sprinkler Syste111sin One- and Two-Fn111ily Dwellings a11dMm111fnct11red Homes, or NFPA l 3R, Standard for the I11stnllatio11 of Sprinkler Systems i11Residential Occupancies Up to and I11c/11di11g Four Stories in Height (FIGURE 38-3).

FIGURE 38·3Viking Model M-1 horizontal sidewallresidential sprinkler.

499

SECTION3: Occupancies

VOLUNTARY INS ECTIONS Fire inspections condu cted in one - and two -fomily dwellings most frequ ently are voluntary fire prevention inspections don e at the request of a homeowner to help eva luate fire safety. In addition to referring the hom eowne r to the "Safety Information" tab at www.nfpa .org, consider offeri ng the following recommen dat ions to help the ho meowner maint ain a fire-safe home.

Utilities All gas, elec tric, and oil-fired utiliti es and applian ces should be kept in goo d repa ir and serviced as n eeded . The homeowner sho uld be instru cted on th e prop er installation and use of electric al extension co rds, portab le heaters, fireplaces, and wood -burning stoves. Damaged light and appliance cords sho uld be replaced. Empha size to the homeow ner tha t all major electrica l work sho uld be done by a licensed electricia n.

Coal- and Wood-Burning Stoves Coal - and wood -burning stoves warrant special attentio n because of their reco rd as a cause of fires. Stoves sho uld be inspec ted very care fully for the adequacy of the insta llation and the clearance of the stove and its chimn ey co nnector from combustibles. 1he au thorit)' havi ng juri sd ictio n mig ht have specific requirements for the instal lation of stoves . If there are no specific local requ ireme nts, ask the homeowner whet her the stove was installed acco rding to the manufacturer's instructions . TI1ere shou ld be a minimum clearance of 36 in . (9 1.44 cm) between th e stove and combustible walls and ceilings. The stove should be po sitio ned on a base of noncom bustibl e material, such as metal or brick, extend ing at least 18 in. (45.7 cm) beyond the stove in all directions . TI1e stovepipe, or conne ctor, between the stove and chimney sho uld be as sh ort and straight as pos sible, and th ere shou ld be at least 18 in. (45.7 cm) of clearance bet ween the pipe and combustib le surfaces. Occu p ants sho uld be reminded that creosote accum ulations both in the connector and the chimney, which form very qu ickly in airtight chi mn eys tha t are not used prop erly, are a dangerous fire hazard. TI1e)'should be advised to have the chimney inspec ted frequently and cleaned when necess ary to prevent chimn ey fires. See NFPA 211, Stmuinrd for Clri11111 eys, Fireplaces, \le11ts , n11dSolid F11el -B11mi11 g Applin11ces,for requirements for proper clearances, and modifications that might be pe rmitt ed, for heating ap pliances. TI1e NFPA FireProtection Hn11db ook also has in formation on haza rds and protec tion of coal- and wood -bu rn ing stoves.

Storage TI1estorage of flammabl e and comb ustible mat erials with in the home shou ld be con trolled. You should check the way in which paint , so lvents, gaso line, and oth er materi als are store d in th e work shop areas. TI1ese materia ls must be stored away from ignition sources and preferably outside the home. Man)' homeowners do not und erstand that flam mable liqu ids produ ce vapors th at can be ignited by the furn ace, hot water heater, or other devices.

500

CHAPTER 38: One- andTwo-Family Dwellings

There is no substitute for good housekeeping. Storage areas should be checked for accumulations of trash and large amounts of combustibles, and these housekeeping problems should be brought to the attention of the occupant.

Detection Equipment Smoke alarms should be installed in all one- and two-family dwellings. You can recom mend which type to install and where they should be placed. Ionizat ion and photoele ctric smoke alarms are comparable, and either type can be used in residential occupancies. The smoke alarms should be located near the sleeping areas of the house, with at least one smok e al.in n located on each floor, and they should be audible throu ghout the house. Because single -station battery -operated smo ke alarms are so easy to install and are allowed in existing one - and two-family dwellings, they are the most common . Explain to the hom eowner that the smoke alarms should be tested on a regular basis lo ensure the batteri s are workin g. l11e batteries should be repla ed on a regular schedule, as well.

Fire Extinguishers Hom eowners will most likely have questions about type. size, location, and number of fire extinguishers. For this information, refer lo NFPA 10, Standard for Portable Fire Extinguishers, but assist the occupants by summarizing the different types, such as carbon dioxide, dry chemical, and multipurpose dry powder. TI1e weight of the extinguisher should be a consideration in the decision of which size to buy. You should advise the occupants to become familiar with the operation of the extinguishers and to practice using them. Occupants should also be referred to NFPA 10 and the manu facturer's recommendations for inspection, testing, and servicing of the extinguishers.

Residential Sprinklers The use of residential sprinklers in one - and two -family dwellings is an increasing trend in some jurisdictions, either by nrnndate or voluntary installation. All sprinklers should be inspected visually to ensure they are not painted over and that their discharge patt ern is unobstructed. All water flow devices , alarms, pumps, water tanks , and other component s of the S)'Stem shou ld be in prop er operating condition. Valves should be inspected to ensure that they are open. Point out that, according to NFPA 13D, proper maintenance of a sprinkler system is the responsibility of the owner, who should understand how the system operates.

Fire Escape Plan Help the homeowner establish a fire escape plan from each room of the house and emphasiz e that once the plan is made, ii should be practiced. ll1e NFPA pamphlet E.D.l. T.H.- Exit Drills i11the Home is a good reference. TI1e following principles of E.D.l. T.H. are simple and sound: 1. 2.

Have smoke alarms on each level of the house and make sure they work. Know two routes to the outside from all rooms, especially bedrooms. 501

SECTION 3: Occu pancies

3. 4.

5. 6. 7.

8.

Have everyone in the house memorize the fire department telephone number, and put the number on the telephones in the house. Choose a place outdoors for everyone to meet for roll call. Locate the closest telephone or emergency call box from which to report a fire in the home. Never go back into a burning building. Practice escape routines-testing closed doors for fire on the other side, crawling low under smoke, and getting out of bedroom windows. Know what to do if occupants become trapped.

You can help the family make an escape plan by reviewing potential escape routes from sleeping areas, pointing out alternatives that might be available, and demonstrating the proper techniques for testing doors for fire and for exiting through windows. Your interest might help to convince a family that E.D.1.TH. is serious business. NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Catalog for availability of curren t editions of the following documents. NFPA 10, Standardfor Po/'fa/JleFireExtinguishers NFPA 13D, Sta11dardfor the J11stnllationof Sprinkler Systems i11011e- and Two-Family Dwellingsand Ma1111fnctured Homes NFPA I 3R, Standardfor the J11sta/lation of SprinklerSystems in Residential Ocwpa11cies Up to and Incl11di11g Fo11rStories in Height NFPA 72®,National FireAlarm and SignalingCode NFPA 101®,Life Safety Code® NFPA 211, Standardfor Chi111neys , Fireplaces,Vents,and Solid Fuel-BurningAppliances

502

CHAPTER

39 MERCANTILE OCCUPANCIES Joseph Versteeg

Mercantile occupancies often requi re more thorough inspections than those for other occupancies. Mercantile occupanc ies include shopp ing cen ters, department stores, drugstor es, supermarkets, auction rooms, big box and other hypermarkets, and any occupancy (or portion thereof) that is used for the display and sale of merchandis e. Commonly, the cause of fire within mercantile occupancies is attributed to cooking, smoking, or elect ricity.

OCCUPANCY CHARACTERISTICS The term mercantile encompasses many differe nt type s of materials and operations. Insp ectors are jus t as apt to inspect a store dealing in glassware as one that sells a large number of paper products or consumer fireworks. Large department stores have a wide variety of products that react difterently in a fire situation. In the past, the great majority of combustible material found within any mercantile occupancy has been Class A mate rial, which includes products made of wood, paper, or cloth. Tilese days, however, th ere are more plastic items or plastic materials that are designed and manufactured to look like something else, such as plastic baby cribs that look, and even smell, like wood. Plasti cs in their various forms are introducing higher than normal fuel loads into sales and storage areas, and th.is fact should be considered when determining the overall fuel load, because when plastics burn, a more rapid fire growt h can occur, resulting in production of heavy, thick. black, toxic smoke. Currently, there is no restriction on the use of plastics in fu rn itu re or other consumer products, nor is there a restriction on the overall amount of the material permitted in a mercantile occupancy . 1lle separation and treatment of other occupancies found within or attached to a mercantile occupancy are other factors inspectors will have to be concerned with, Class A stores (defined below) often contain nonseparated cafes and daycare facilities, where the children of shopper s are attended to temporari ly while the parents shop . In large shopping malls, a variety of diflerent mercantile occupancies will often, in one way or another, connect to several assembly occupancies. In this case, inspectors must consider

SECTION 3: Occup ancies

the different occupant load factors, for example, behveen a restaura nt that may be found in the mall and a departm ent store. When inspecting the premises, inspectors should use the same walk-through process to familiarize themselves thoroughly with the building; after all, the)' may have to visit the building under fire condition s someday. VVith this approach, they will be able to make educated decisions as to the probable occupant load when a fire alarm does sound . NFPA 101®, Life Snfety Code®, separates mercantile occupancies into three subclassifications. A Class A mercantile occupancy is any store having an agg regate gross sales area larger tha n 30,000 ft2 (278 7 rn2) or a store using more than three floor levels for sa les purposes . For examp le, a single-s tory store with 32,650 ft2 (3033 1112)of gross sales area is a Class A mercantile occuµanc)'; a four-stu1 )' spor ting goods store::with 20,000 ft2 (1858 m2) of gross sales area is also a Class A mercantile occupancy. Inspectors should also remembe r to measure the total sq uare footage (gross) instead of only the floor area not covered with stock of some sort (net). A la · B mercantil e occup ancy is any stor e with less than 30,000 ft2 (2787 m 2) but greater than 3000 ft2 (279 m2) of aggregate gross sales area or one that uses any balco nies, mezzanines, or floors above or below the street floor for sales purposes . The except ion to this is one of the examp les used above for Class A mercantiles: a four-story, 20,000-ft2 (1858-m2) space that is Class A regardl ess of the size. A Class B mercantile 2) th en is the h,'o-story, 25,000 -ft2 (2322 -1112)department store or the 4000 -ft2 (372 -111 drugstore. Class C mercant ile occupancies are all stores with 3000-ft2 (279-1112)or less of gross sales area on only one story. In addition to the traditional store categories, NFPA 101® also contains provisions for covered mall buildings and b11lk merchandising retail buildings where the disp lay of mercha ndi se is 011 pallets, in piles, or on racks in excess of 12 ft (3.7 rn) in height.

INSPECTING HE PREMISES \,Vhen beginning the i.nspection of any mercantile occuµa nc y to determine compliance with NFPA 101® and other pertinent Nntionnf Fire Codes®,as well as with the building codes and ordinances of the jurisdiction, you should get an immediate and general idea of what level of maintenance is carried out by the store statt: If the area is somewhat cluttered, with questionable aisles and unswept floors, the chances are good that the entire store will look that way or worse . Poor housekeeping is an indication of the general level of conscious fire safe ty behav ior practiced in that particular store and of how much of a task you face. Attent ion shou ld be paid to seasona l displays that often block exits and /or reduce required aisle w idth.

Occupant Load TI1e occupant load for 1nercantilc occupancies as estab lished in NFPA 101® is 30 ft2 (2.8 m2) of gross floor area of sales sp ace pe r person on the stree t floor or sales floors below the street floor; 60 ft2 (5.6 1112)of gross floor area of sales space per person on upper floors used for sales; 100 ft2 (9.3 m 2) per person on floors or portions of floors 504

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used onl)' for offices;and 300 ft2 (28 1112) of gross floor area per person for those floors or portions thereof not open to the general public but used for storage, shipping, or receiving. NFPA 101® has special provisions for malls based on the gross leasable area. Although the occupant load is not specifically required to be posted in a conspicuous place within the store, it is a good idea to suggest doing so to the manager. That same occupant load should be recorded on the inspection sheet when prefire planning is conducted in the building, so that you will know what occupant load to expect in the event of a fire.

Means of E r s Various types of means of egress are allowed from any mercantile occupancy, such as stairways, smoke-proof towers, doors, ramps, and, in some cases, escalators. Still others require the approval of the authority having jurisdiction for ver)' special applications, such as revolving doors or fire escape stairs. Fur the exact application of each type of egress component, refer to Sections 36.2.2 and 37.2.2 ofNFPA 101®. Generally speaking, al least two exits must be provided and be accessible from every part of every floor and especially from floors below the street-level floor; however, NFPA JOI® does permit a single means of egress in Class C stores under limited conditions. Ex.itsshould be located as far apart as practical, but generally not closer to one another than one-half the longest diagonal distance of the space served in new stores or new arrangements . ln a grocery, discount, or variety store where checkout stands and turnstiles are provided to restrict exiting, at least one-half of the required exits in both number and c.1pacitymust be provided in such a manner that they can be reached without having to go through the turnstiles and checkout stands. You will find that this requirement is commonl>•violated, although its purpose is clear. In a fire or other emergenC)',persons within the space must be .-.bleto exit quickly and easily, without any obstructions to that exit travel. Generally speaking, all egress doors are required to swing in the direction of exit travel, particularly (1) when used in an exit enclosure (e.g., stairway), (2) when serving a high-hazard area, or (3) when serving an occupant load of 50 or more persons. A common misconception is that all exterior exit door s are required to swing in the direction of egress travel regardless of the occupant load served. Although special locking features are allowed in some configurations, the fundamental rule is that all locking devices on egress doors must be operable without the use of a key or special knowledge, and the method of operation must be obvious even in darkness, with a single operation needed. Often found during inspections are rear exterior doors barricaded against crimi nal break-in attempts that also impede egress. No occupants of any mercantile occupancy should have to travel more than 150 ft (46 m) (150 ft (45.7 m) in an existing unsprinklered mercantile occupancy! to find the exit nearest them . 'TI1isdistance can be increased to 250 ft (76 m) in those buildings protected throughout by an approved automatic sprinkler system. In some instances, exit access can p.1ssthrough the storerooms of mercantile occupancies, but only if (1) at le.1st one other me.-.nsof egress is provided, (2) the storeroom is not subject to locking, (3) the main aisle through

sos

SEC ION 3: Occup ancies

the storeroom is not less than 44 in. (l.l 111)wide and in the clear, and (4) the main path of travel throu gh the storeroom is obvious, has fixed barriers, and is completely unob structed. These hidd en areas are prone to being blocked by deliveries and trash awaiting pickup. Emergency lighting is requ ired in all Class A and Class B mercantile occupa ncies. Class C stores, because of their small size and occupant load, are not required to have such installations .'Em'ergency light ing installed on walls prior to tenant fit-up is of1en rendered useless when blocked or located behind items on shelves. To facilitate law enforcemen t arrest and detention activities, mercantile occupancies permit the use of lockup facilities as discussed within Chapter 33, Detention and Correc tions Occupancy, of this text.

Protection of Openings Ver tical openings in all mercantile occupancies arc required to be enclosed or protected in some manner , but the exceptions to this are numerous. Refer lo NFPA 101® for ench specific application. The special mies that allow mall buildin gs, for example, to have multiple levels open to a common atmosphere requires compliance with additional features such as smoke control systems, arrangement of the pedestrian way,and other elements that must be evaluated on a case-by-case basis.

Protection of Hazards Any area of the space that creates a greater hazard than other areas of the occupancy is required to be separated from those other areas by construction having 110 less than a 1-hour fire-resistance rating, or it must be protected by automatic sprinklers. Areas requiring this special protection include maintenanc e closets, fuel storage areas, maintenance shops, general storage areas, boiler or furnace rooms, and kitchens. Any areas with contents cons idered to be highl)• hazardous, that is, liable to burn with extreme rapidity or result in an explosion, are required to be both separated by construc tion with at least a ! -hour fire-res.istance rating and must have complete automatic sprinkler pro tection. It is up to the authority having jurisdiction to determine what degree of hazard the contents represent and then to make a case for that decision .

Interior Finish Interior finish for walls and ceilings .is required to be eithe r Class A or Class B, except that existing Class C interior finishes are allowed on walls only (not ceilings) and in existing Class C stores (see Chapte r 23 for further discussion and tlame-spread ratings). Inspectors should use reasonable discretion when determining what the existing finish is and, ifit is noncompliant according to code, what reasonabk methods should be required to correct the violation. TI1ereare no specific prohibitions concern ing floor finishes. However, if you find a floor finish that presents an unusual hazard, Section 10.2.2.2 ofNFPA /OJ® gives the authority having jurisdiction power to regulate it. 506

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FIRE PROT CTION You will need to det ermine which type of por table extinguishers are available, if they are fully serviced and operational, and if th e number pro vided is sufficien t for th e space. 1he general rule is that at least one hand exting uisher of at least a 2A: lOBC rating be available within a trave l d istance not exceeding 75 ft (23 m) and tha t at least one 2) of floor space. Refer to the pertine nt should be provi ded for every 3000 ft2 (279 111 g 11i shers, for furt her information. sect ions of NFPA I 0, Strmdnrdfor Portable FireExti11

Alarm Systems All Class A stores, covered malls, and bulk merchandising retail buildings are requir ed to have a man ual fire alarm system throughou t the building; however, build ings pro tected thro ughout by an approved automatic fire de tection and alarm initiation system or protected throug hout by an approved au tom atic sprinkler system that prov ides alarm initiation are requ ired to h ave only one manual fire alarm box. An alarm system , if present, should have manual fire alarm boxes al each exit and should also activate th e fire alarm system in the event one of th e manual fire alarm boxes is activated. Whether requir ed or not , the system should be maintained in an operational condit ion. Jf peo ple see a manual fire alarm box, they naturally assume that it will work when needed.

Sprinkler Systems Approved automatic sprinkler protection is requi red (1) in all mercantile buildings having a story greater than 15,000 ft2 (1400 m2) in area, (2) in all mercantile buildings exceeding 30,000 ft2 (2800 rn2) in gross area, and (3) throughout all stories of the occ upancy below the level of exit d ischarge each having an area exceed ing 2500 ft2 (230 m2) and tha t are used for sales, storage, or handl ing of combus tible goods or mercha ndise. Rely on NFPA 101® to ensure that those merca ntile occupancies required to be spri n klered are provided with full spr inkler protection. TI1e requirements for new cons truction are more strin gent. In addition, NFPA 101® also requires covere d mall buildings and bul k merchandising retail buildings to be protected by au tom atic sprinkler systems, regardl ess of size. If an area is required by code to h ave spr inkl er protection and th ere is none, request tha t it be in stalled. If spri nkl er protection is in place, check that no spri nklers are obst ru cted , that they are not painted, and that there are no sales stock decoratio ns or signs hanging from the piping. The sprinld er discha rge should not be obst ru cted by sales stoc k. All areas of the sto re should be protected b}' sprinkler protection, and the contro l valves and inspector 's test pipes sh ould be easily accessible by engi ne crews and test pe rso nn el. Also check the design densities under which the sprinkler system was installed. If the densities are not n ow sufficient for th e produc ts being protected , the system should be upgraded to ens ure th at the system wiJI do wha t it is being cou nted on to do na mely, to control a fire. If the spr inkler system was designed as an ordi na ry hazard grou p 1 system but is now prote ct ing large amou nts of plastic material, or a much 507

SECTION 3: Occupancies

greater load of Class A material or perhap s a storage area with flammable or combus' tible liquids, that system will not perform as expected, and it should be upgraded to meet the new demands. If you arc not sure whether the sprinkler S)'Stem will perform as it was designed to, consult the fire department plans reviewer, fire marshal, fire chief, or building official to ensure that the protection is still adequate. If some other form of automatic extinguishing system is present in the facility (such as a dry chemical system inside a cooking hood), that system should be fully operational and should have been serviced within the last 6 months. All nozzles must be unobstructed, and cooking should be done only under the hood (see Chapter 61, Protection of Commercial Cooking Equipment).

Covered Malls Covered malls require special considerations when it comes to inspections and code compliance. Most shopping malls are arranged so as to be classifie I as a mall building with anchor stores. Caution should be exercised when classifyingolder shopping malls, because they may not meet the cr iteria for a mall buUding and therefore may be simply a large Class A store. For the most part, a covered mall and all the shops that open into it are required to be folly sprinklered. NFPA 101® provides numerous requirements for egress arrangement, egress widths, and travel distances to exits. A common feature in mall building .is an exit passageway. Exit passageways function in a manner similar to an exit stair, in that the exterior atmosphere is brought closer to the occupant by a highly protected path of travel. A fire alarm system that is activated by the mall smoke detectors or automatic spr.inkler system is required within a covered mall; however, manual fire alarm boxes are not required. A smoke-control system typically must also be provided in covered malls. TI1estore area must be neat, with aisles organized as required by NFPA 101®. TI1e storage or display of hazardous commodities, such as flammable liquids or gases, combustible liquids, pesticides, or oxidizers, should be in compliance with the appropriate NFPA code or standard. NFPA Codes, Standards, and Recommended Practices

See the latest version of the NFPA Catalog for availability of current editions of the following documents. NFPA 10, Standardfor Portable FireExli11g11ishers N FPA 13, Standardfor tirelllsta//ation of Spri11klerSystems NFPA 30, Flammable and Co111b11stible Liquids Code NFPA 72®,Natio11alFireAlarm and Sig11ali11g Code NFPA 101®,Life Safety Code®

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CHAPTER

40 BUSINESSOCCUPANCIES Jos ph V,,rsteeg

NF PA IOI®, Life Safety Code®, defines business occupanc ies as those used for the transaction of business, the keeping of acco nn ts and reco rds, and similar purposes . They includ e general offices, doctor s' offices, government o ffices, city halls, municipal office buildings, courth ouses, outpati ent medical clini cs where patients are ambulatory, college and university classroo m bu ildings with less than 50 occupants, and instru ct iona l laboratories. Business occupan cies typically have large numb ers of occupan ts during normal business hours and very few occupant s du ring nonw orking hour s.

OCCUPANCY CHARACTERISTICS Bus iness occ upanc ies can be in buil d ings of any constr uction type perm illed by local buil d ing codes; NFPA 101® does not specify construction requirement s for bus iness occupancies. With the exceptio n of parking struc tu res regulated b)' NFPA 88A, Stn11 dcmlfor ParkingStructures, NFPA 10J® does not spe cifically require business occupancies to be separated from ot her occupancie s when arranged as m ixed occupancies in a multiple -occupancy building. Howe ver, where busin ess occupancies are not arran ged with othe r occupa ncies as mi.xed, NFPA .101® will requi re compliance with th e criteria for separated occupan cies. Note that local buildi ng codes might req uire occ upan C)' separation, usually with at least 1-hour fire-resistive co nstru ction. In mix ed occ upa ncies, NFPA 101® requirements for bot h occupancies must be satisfied. In othe r words, NFPA 101® requireme nts for both occupancies are applied sim ultaneous ly. ' "'here there are d iffering req uiremen ts, the requirem ents afford ing the high est level of safety must be applied. Busine ss occupancies traditionally have been subdivided into many small office spaces . Although don e for other reasons, these subdivi sions compartmentalized an otherwi se large floor area. '0 1e advent of open -plan office space, however, has, for the mos t part, take n away these natura l fire barr iers. In an open- plan design, lar ge floor areas are subdivid ed int o cubicles using office furniture and pa rtiti ons that do not extend from the floor to ceiling. Fire can spread mor e qu ickly from one wor kstation

SECTION3: Occupancies

to another because of th e exposed combustibles. One advantage of th e open -pl.in arrangement, however, is that occupants are usuall)' able to detect a fire quickly because they have an open view of th e floor area. Business occupan cies are generally thought to have a light -hazard fuel load. Although the fuel load in office Sp.ices from wood furniture and trim has declined since the 1940s, .it has incre ased because of the use of more paper in office operations and the use of more plastics and other synthetic materials in furnishings and equipmen t. Because of the increase in the use of synthetic material, mostly plastics, the concept of fuel load shou ld be used carefully as a predictor of fire severi ty. Synthetic products often have high heat release rates, which causes fires of th ese materials to be more severe than those of an eq ual volume of wood. In addit ion, business occupancies often have significant fuel loads that are not fixed or constant. 1l1ey include delivered materials, as well as furniture, recyclables, and trash that is awaiting removal from the buildings. More extensive use of recycling programs for items like pap er, cardbo ard and plastic bott les now provide concentrated fuel load s tJ1at were praclfrally nonexistent 10 or 15 years ago.1l1ese fuels are usually found in aisles and corridors, which increase s the threat to life safety. A fire load analysis cannot be considered complete without an estimate of the transient fuel loads expected in th e building. Although building occupancies typically have light fuel loads, large life loss fires can occur in them during norma l working hours, because the occupant load can be up to one person for each 100 ft2 (9.3 m2) of gross floor area. The sign ificant transient fuel loads also con tr ibu te to this potentia l problem. Business occupancy floor plans change often, and these renovations can cause a properly designed means of egress to become non com pliant, partially obstructed, or blocked. Renovations can also be a source ofignilion, increasing the chance of fire. One of the first tasks during an inspection is to determine if there will be or have been any recent cha nges or renov ations lo the building or changes to floor plans.

INSPECTING THE PREMISES Means of Egress The basic requirements of means of egress for other occupancies also apply to business occupancies . There should be two remote exits from every floor, with some lim ~ ited exceptions, and egress trav el paths should be illumin ated and iden tified by proper signage. 1l1e exits must be located in a way that will reasonably redu ce the possibility of both exits being blocked by a single fire incident. In some instances, there can be only one exit but with specific limitations associated with it. 1l10se circumstances are described in Chapters 38 and 39 ofNFPA 101®. When two exits are required, they must be remotely located, and they must have separate paths of travel. 1l1e access to the exits, as well as their discharges, mu st also be located so that a single fire would not block both exits. 1\vo ex.its discharging through a common lobby do not meet this requirement . One of the most prevalent problems in business occupancies is excessive common paths of travel. Chapter 22, Means of Egress, covers this topic. 510

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Tf occupan ts must walk through corridors to reach exits, the walls separa ting the corridors from the adjacent spaces must be I -hour fire barriers in new occupancies. Excep tions to this requirement are permitted for some existing occupancies (depend ing on which code edition is in use), single -tena nt spaces, and in spaces pro tected by automatic spr inkl ers. NFPA 101® gives requirements for permissible corridor wall penetrations and required protection of openings. 'TI,c exit discharge is probabl) ' the most overlooked porlion of the means of egress. All the requirements pertaining to an unobstructed path of travel and illumination apply to the t:Xit discharge even though the exit discharge is genera lly outside the building leading to a public way. When emergency lighting is required, the exit discharge must also have some degree of emergency lighting. TI1eexit discharge must be kept free of obstruc tions, and there must be a reliable method for preventing ice and snow from accumulating in areas subject to such weather conditions. Dumpsters are one examp le of an item that is often tim es located near the exit door. Check the areas around the exit doors to dctcrm ine if there is an)1 thing unusual that could cause problems in an emergency. Heigh tened security measures, includin g exterior fences, are often installed, many times without the approva l of the authority having jurisdiction (A HJ). Be aware of an)' such changes and ensure tha t exterior exit discharge remains readily available and clear, all gates through occupant egress satisfy the doors cr.iteria of NFPA 101®, and that fire department access to the building remains available. To be useful, exit doors must be accessible. Many tim es, in attempting to lay out an office for best space utilization, litt le cons ideration is given to maintaining clear access to exits. In open -plan office spaces, make sure you are aware of forniture arrangements that obstruct direct access to exit doors. 11lis rearrangement is commonly done without approvals. Exit doors must be capable of being opened from the occupied side at all times . In multiple tenant offices, doors are sometimes locked for secur ity reasons, with little thought given to life safety. Only locking devices capable of being opened by the person seeking egress are pe rmitted. Special locking arrangements, including delayed egress and access -controlled doors, are permitted and usually can be arranged to solve security concerns . 'n1e exit itself must be accessible and unobstructed. Locking of stair doors is a common problem that you must look for. You should walk the stairs from top to bottom to ensure the path of travel is unobstructed. Doors at the termination of exits must be obvious and op enable. Stair doors should not be locked from the sta ir side so that people using them will not get trapped if there is a fire in the stairway. If stair doors are locked from the stair side, ther e must be some method of unlocking them, or some floors shou ld be designated to remain unlo cked. NFPA 101® permits two methods for reentry in business occupancies. TI1e first is electric locking devices that automatically unlock (but not unlatch) doors, allowing reentry upon the activation of the building fire alarm system. TI1esecond method requires that at least two doors for reentr)' be provided in each stair, one of which must be al the top or the next -to-top floor. In stai rs serving five stories or more, reentry doors must be provided, so that there are no more than four intervening floors between unlocked doors . 5ll

SECTION 3: Ocwpan cies

Travel distance is also an importan t life-safety requirement, but care must be taken to ensure that the travel distance requirement is met in a reasonable way. Some open floor plans can be arranged in such a way that the furniture creates a maze, which greatly hinder s occupants who are trying to lenve the area. Exits must be marked in business occupancies, and exit signs should be placed to properly mark exits and access to exits that are otherwise not readily apparent. NFPA JOJ® requires exit signs to be placed in corridors so that a person i not more than JOOft (30 m) from an exit sign at any point in the corridor. fn buildings with open floor plans, the exit signs must properl}' mark the path to the ex.it. In occupancies with floor plans using low height partitions, the signs might be visible from a greater distance, but the floor plan might prohibit direct travel to the xil. Tirns, it might be necessary lo place some signs on the partitions. Although internally illuminated exit signs are not required, all exit signs must be illuminated in some way. If emergency lighting is required, the exit signs must also be illuminated by the emergency lighting source. lien, a pla ard-type sign lit by emergency lights will meet this requirement.

Protection of Floor Openings Unenclosed floor openings between stories have become an extremely popular design feature in both large and small officebuildings. Floor openings, such as atria, mini-atria, light wells, and convenience stairs can be both a problem and a benefit, dependi11gon their size and location in the building. Such openings present a fire safety problem, because heat and smoke have the ability lo spread readily from floor to floor. For this reason, review the requirements in NFPA 101® for the protection and permitted location of unenclosed !loor openings. vVhere the floor openil1gs are enclosed by shaft construction, all openings in such fire-rated walls should be protected with doors or other approved opening protective devices. Check the doors to ensure that they close and latch properly. Closing devices are required on fire doors, and they should function properly. A labeled door leaf, door frame, closer, and latch are required. Any wedges used to hold doors open should be removed immediately. Automatic hold-open -and-re lease devices should be used on fire doors that, for functional purpo ses, need to remain open daily. \'\'indows in fire barriers and doors must be of fire-rated glazing (usually wired) or an approved material in steel frames. 1here are also transparent glazing materials that can be used as a .fire-resistive barrier. Review any information available on such material carefully. [11 rated walls, windows of plain glass or wooden or aluminum frames should be replaced with properly tested and rated assemblies. 'll1e integrity of shafts and chases is as important in business occupancies as it is in an)' other occupancy. When new buildings are constructed, utility risers are usually enclosed in fire-rated shafts, and floor penetrations are sealed with appropriate fireresistive materials. As buildings arc used, new cable, conduit, or piping is often run between floors, and the new penetrations may not be properly sealed. You should check telephone and electrical closets and mechanical shafts and risers to determine if there are unprot ected floor openings or penetrations through fire

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barrier walls. Such open ings can be sealed with lightweight concrete or other suitable materials, such as silicon foam.

Hazardous Areas General storage rooms, boiler rooms, fuel storage rooms, janitor closets, and maintenan ce shop s are conside red hazardous areas and should be separa ted from the rest of the building by I-hour fire-resistance rated cons tru ction; opening s should be protected by ¾-hour fire door assemblies. If hazardou s areas in new and exi ting construct ion are protected by sprinklers, they need only to be enclosed by smoke partitions, and the openings should be prote ct d by self-closing or automatic closing, smoke -re istant doors . Common now within office buildings are kitchenettes containing a residential type stove, refrigerator, and several vending machines. Although these typically do not require any added protection, inspectors should be aware that the use of the stove is limited to food warming.

Computer Rooms Electronic data processing equipment has become both vital and commonp lace in many businesses. This equipment can be highly soph isticated and extremely valuabl e; in fact, both the equipment and especially the data can be unique and may not be for the Protectio11 of ElectronicComp11 ter/Dntn able to be repla ced . NFPA 75, Stn11dnrd Processi11g Equipment,contains more detail ed requirements for fire protection for electronic computer/data process ing equipment and computer areas.

Protection of Records Evaluating the worth of records, no matter what kind they are, is a management responsibilit}' in which your only responsibility is to provide information on possible exposure to loss; therefore, be prepared to tel.I management what different levels of protection are available for records of different value and vo lume. More specific information and requirements for the protection of records is available in the FireProtectionHandbookand in NFPA 232, Standardfor the Protectionof Records.

INSPECTING BUILDING SERVICES Waste Disposal Business occupancies can generate large amounts of waste paper . Usually, this waste is removed from the general office areas at the end of the day. TI1is collected waste can create a significant fuel load in corridors, freight elevator lobbies, or where it is held for disposal. Recycled materials may be collec ted at a central point, but containers might be emp tied only ever)' 2 to 3 days or even at less frequent intervals. TI1eprincipal concern is how waste material is hand led after it is collected from the various offices and workstations. Smoking materials improperly discarded into trash collec tion containers have ignited 513

SECTION3: Occupancies

other tr,\sh in the contai ner s, and these fires have spread to other areas. Thus, specia l precautions to prevent this situation should be taken. Precautions .include use of specially des igned con tainer tops and discarding of smoking materials into noncombustible cans and allowi ng them to cool before they are disposed of. Smoking bans inside most types of ofllce buildings have all but eliminated this ignition scenario, but the concentrated quantity of material is still present. All waste should be removed from th e building quickly. If it is stored within the buildi ng for short periods oft im , the waste should be in proper containers or stored in specially desig ned rooms. TI1e practice of piling up waste in plastic bags in eleva tor lobb ies or corridors while awaiting its removal can have disastrous results. Once waste is removed from the building, it is usually held in outside storage bins (dumpsters) for frequent rem oval from the premises. If that is the case, observe the general condition of the outside storage area. 11shou ld be far enough away from the building so that it does not present a fire exposure to the building. Sturdy enclosures around trash storage areas can discourage vandalism and unauthoriz ed dumping, both of which can lead to dumpster fires. With paper recycling and sh redd ing becomi_ng more common in oft1ce buildings, centralized collection areas can deve lop a greater concentratio n of paper and hence more fuel than what typ ically may be found in such areas.

Cafeterias Many large bu siness occupancy buildings have their own cafeteria facilities and kitchens. If the area has an occupant load of 50 or more persons, the area is classified as an assemb ly occupan cy. If the occupant load is less than 50 persons, the area is considered an incidental assembly use area and subject to the requirements of a business occupancy. If classified as an assembly occupancy, determine wheth er to evaluate the combination as either a mixed or separated, multiple occupanc}'- In addition, examine the kitchen equipment for evidence of g rease accumula tions in hoods and exhaust ducts; good duct installations will have cleaning and inspection openings. Hoods, exhaust ducts, and grease remova l devices must be protected by approved extinguishing S)'Stems,which usually consist of fixed-pipe carbon dioxide, dry chemical, or foam sprinkler or spray systems. If there are no special extinguishing systems, the cooki ng equipment might be served by a listed or labeled grease extractor, which may provide sufficient protection . TI1ecooking surfaces of fat fryers, ranges, griddles, and broi lers, which can be a source of ignition, also need to be protected by appropriate extingu ishing systems. You should make su re that instructions for manually operating the fire extinguishing systems are posted conspicuously. Asking kitchen employees how the systems operate shou ld give you on .indication of how familiar they are with the systems . Check the log to determine when the spec ial systems were last serviced and inspected; they should be inspec ted and serv iced every 6 months. In addition, make sure there are eno ugh portable fire extinguishers suitable for Class B and Class C fires near the cooking equipment. If the fixed exting uisher uses a dry chemica l extinguishing agent, make sure that the portable fire exting uishers in the area are compat ible with it. For example, if tl1e fixed system uses a llC dry chemical, the portable extinguisher should also be BC, not ABC. Be sure to note when the portable exting uishers were last inspected and serviced. 514

CHAPTER 4 0 : BusinessOccupancies

See the discussion on protection of comme rcial cooking equ ipment elsewhere in Co11tro l mid Fire Protectio11of Co111 this text and NFPA 96, Stn11dmdfor \1e11/i/ntio11 111 ercinlCookingOperntio11s, for more comp lete information about and spec ific requirements for kitchen cooki ng equ ipmen t installations .

IR PR T

TIO N

Automatic prinklers Automatic spr inklers are genera l!>' req uired in high-rise business occupanc ies (those that are h igher tha n 75 fr (23 m) when measured from the lowest. level of lire department access to the highest floor tha t may be occupied) . TI1espri nkler system must be elec trically sup ervised. In lieu of sprink lers, cxjsting buildings can be eq uipped with an alternative equivalent system app roved by the AHJ. TI1eadeqnaC}' of sprinkJers, or an equivalent system, depends on several basic condi tions. TI1e hazard severity must be analyzed to ensure that the protect ive system is sufficient to control a fire. TI1eimpact of the expec ted fire must be judged to determine its effect on the occupants .ind the rest of the building. TI1e occupants' response, both first aid firefighting and ability to escape, must be determined as part of the incident imp::ict. You can use this information to determine whe ther adequ::ite protection is prov ided. Spri nkler systems, altho ugh high ly reliable, requi re regu lar inspection. testing, and maintena nce. Ensure that alJ spr inkler valves, including water supp l)', are open and locked or superv ised in th.it position . Closed w::iter suppl y valves .ire the most com mon cause of sprink ler system failures. Find out whether there is a procedure for en suri ng that sprinkler valves are closed only when properly authorized and tu rned on again after an)' rnainterrnnce or modificati on. Records of spri nkler system testi ng and mai nt ena nce shou ld be checked. See th e discussion on automati c spr inkl er and other water-based fire protection systems earlier in thi s text for details about inspection of automat ic sprinkler systems. Because oflegal liabili ty issues, the ju risd iction should have a po licy regarding test ing of systems; in general , the building owner or representative shou ld do all the testing. You should witne ss any tests required to be pe rformed as part of an inspec tion.

Alarm Systems A manual fire ala rm system and an emergency lighting system are required when a bus iness occup.11JC)'is two or more stories above the level of exit discharge, when the occupan t load abov e or below the level of exit d ischarge is 50 persons or more (300 or more in existing buildings), or when the occup::int load of the bu ilding is 100 persons o r more (1000 or more in existing build ings). ln ad dition, at least one manual fire alarm box is still required 011 premi ses tha t can activate the buildin g fire alarm system. '"'hen the buildin g is full)' spri nklered or totally prot ected by an auto m::itic fire alarm S)'Stem, manual fire alarm boxes .ire not requir ed if the sp rink lers or automati c system cause the evacuation ala rm to sound. As with au toma tic spr inkler systems and because of poor maint enance in many bus iness occupa ncies, yo u should on ly witness the tests, with the buildi n g owner or represent::itive doing the actual testing. 515

SECTION3: Occupancie

Portable Fire Extinguishers Portable fire extinguishers are required in business occupancies. The)' should be used, placed, and maintained in accordance with NFPA 10, Standard 011Portable Fire Extinguishers,and state and local laws. You must examine testing and maintenance records to ensure that the extinguishers are being prop erl)' tested and maintain ed.

Special Provisions In addit ion to determining the degree of compliance with the requirements of Chapters 38 and 39 ofNFPA 10/ ®, be aw,1reof the often-overlooked additional provisions per-

taining to windowless and underground structures in Chapter 11 of the code. Because of the added concerns unique to these types of structures, requirements in addition to those found within the business occupanc)' chapters ofNFPA 101® may be mandated for these structures with respect to automatic sprinklers, emergency lighting, egress arra nge111 e11Ls,and, i11certain instances, smoke venting.

OPERA ING FEATURES Each occupancy chapter of NFPA 101® contains requirements on operating features. Specific requirements for business occupanc ies include having written emergency procedures and training all occupants in procedures. In addition, emergency egress and relocation drills m ust be held on a schedule acceptable to the local authorities. Employees of the building, usually the operating staft: must be trained in the proper use of po rtable fire extinguishers in the bu ilding.

BIBLIOGRAPHY Cote, A. E., ed., FireProtection Ha11rlbook, 20th ed., NFPA, Qu incy, MA, 2008. NFPACodes, Standards, and Recommended Practices See the latest version of the NFPA Catalog for availability of current editions of the following document s.

NFPA 10, Standard 011PortableFire Exting11i sliers NFPA 75, Stm1dardfor the Protectio11ofE/ectro11ic Computer/DataProcessi11g Eq11ip111e11t NFPA82, Standard011 I11ci11erators and Waste(111d Li11enH(ll1dli11gS yste111 s (IIU[ Eq11ip111 e11t NFPA 86, Standard.for Ovens a11dFurnaces NFPA 96, Standardfor Ventilatio11 Co11 trol a11dFire Protectio11of Co111111ercial Cooking Opemtions NFPA 101®, Life Safety Code® NFPA 232, Stm1dardfor the Protection of Records

516

CHAPTER

41 INDUSTRIAL OCCUPANCIES JosephVersteeg

NFPA 101®, life Safety Code®, defines an ind ustr ial occupanq' as a buildin g, a portion of a building, or a group of buildings used for the manufacture, assemb ly, servi ce, mixing, packaging, .finishing, repair, treatm en t, or other processing of goods or commodities by a variety of operat ions or processe s. Industrial ocrnpancies include , but are no t limited to, the following: l. Chemica l plants 2. Factories of all kinds 3. Food proc essing plants 4. Furnitur e manufacturers 5. Han gars (for servic ing/ma intenance) 6. Laboratori es involving hazardous chemicals 7. Lau ndr y and dry -cleaning plan ts 8. Meta lworking plan ts 9. Plastics manufacture and molding plants 10. Power pla nts 11. Refinerie s 12. Semiconductor manufacturing plants 13. Telephone excha nges 14. Woodworking plants

Each building or separated portion of an indust rial building should be inspected in accordance with the requ irements of its principal use; for example, warehou ses as storage occupanci es, offices as bu siness occupancies, and auditoriums , cafeterias, and .lunchroom s as assembly occupancies. Because of the complexity of industrial occupancies, th e inspect ions can be tim e consumin g.

OCCUPANCY CLASSIFICATIO N Ind ustr ial occupancies are subclass ified in NFPA 101® into three types of usage: gen era l, special purpose, and h igh hazard .

SECTION 3: Occupan cies

• Ge11eml i11dust ri11 / ocwpa11 cy: TI1is subclassification involves ordinary and lowhazard manufacturing operations conducted in buildings of conventiona l design suitable for various types of manufacture, Also included are multistory buildings where floors are occupied by different tenants and, therefore, subject to possible use for types of manufacturing with a high density of employees. • Specialpurpose i11d11strinl ocwpn11cy:TI1is subclassification includes ordinary and .low-hazard manufacturi ng opera tions in buildings that were designed for and suitable on l) for particular types of operations. Such buildings are characterized by a relatively low density of employees, with much or the area occupied by machinery or equipmenl. • High-lwzanl i11d t1strialoccupancy:Buildings in this subclassification include those having high -hazard materials, processes, or contents. Incidenta l highhazard operation s in ordinary or low-hazard occupancies that are protected with automatic extinguishing S)'Stemsor othe r protection (such as explosion suppression or venting) appropriate to a particular hazard arc not considered high-hazard occupancies overall. Some of the common problems encounter ed in industrial occupancies include overcrowding, poor housekeeping, poor maintenance of electrical equipment and wiring, inadequa te exit facilities, locked or blocked exits, misuse of flammable liquids and heat-produ cing appliances, and poor maintenance of fire protection systems and appliances. Code enforcement must be rigid and inspection thorough, with some emphasis on fire safety education and prefire planning .

INSPECTING THE PREMISES Occupant Load The occupant load in industrial occupancies is one person for each l 00 ft2 (9.3 m 2) of gross floor area, and exits that can accommodate this min imum capacity must be provided in these occupancies. In most plants, the space occupied by workbenches, machinery, and equipm ent generally tends to keep the occupancy well within the ratio. So-called "sweat shops;• however, tend to be the exception with their dense concentrations of workers. An increased occupant load is permitted if a floor plan showing that proper aisles and adequate exits are available sarely to accommodate the increased occupant load is submitted to the authority having jurisdiction. ln most instances, overcrowding will be fairly obvious to you during the inspection. In a special purpose industrial occupancy, the occupant load is the maximum number of persons that may occupy the area under any probable conditions.

Means of Egress Requirements for exits in industrial occupancies are found in Chapter 40 ofNFPA IOI ®. Inspectors should be aware of the requirements because they are responsible for seeing that all portions of a means of egress are maintained in a safe and usable cond ition. 518

CHAPTER 41: Industrial Occupancies

All exits must discharge to a clear and unobstructed path of travel to a public way. Where there is evide nce of parked vehicles or other obstructions, signs or barriers should be erected to prohibit the pra ctice. Barriers or fences cannot obstruct the flow of persons exiting the building. Exits must be clearly illuminated, identified, and accessible. NFPA JOI® requires the placement of exit signs at all exits, which in large buildings may not be readily visible to the occupants possibly because of building configuration and most like!>' because of machinery and equipm ent. '" 'here such signs are not readily visible to the occupants, additional signs along the egress path may be required to guide occ upant s to the exit locations. Note that these additional signs are required only where the way to reach the exit is not readily apparen t to the occupants. Frequent evacuation drills are one way to document that occupants know the location of exits. Open every exit door to be sure that it is .labeled when required, swings in the direction of egress travel when so requ ired, and that selfclos ing or automatic -closing devices and mechanisms function properly. v\lhere pilferage might be a problem, means other than locking are availab le to prevent unauthorized use of exits . NFPA JOJ® permits the use of approved, listed, special locking arrangem en ts on doors in industrial occupancies. All conditions set forth for their use must be followed. Delayed -egress locks and access-controlled egress devices do not prevent the door from opening; rat her, they merely delay opening and ma>' require the sounding of an alarm. Special locking arrangements ca nnot be used in high -hazard areas. Where exit stairs are requ ired to be enclosed, the enclosure and its protected openings must be of the proper fire-resistance ratings. Handrails must be secure, and stair treads and landings should be slip resistant. Stairways cannot be used for storage or an>' other purpose, and they must be illuminated. Every worker must have access to not less than rwo remote ly located exits. 1he path of travel must be clear, illuminated, unobstructed, and as direct as possible with out exceed ing maximum travel distances. NFPA 101® has been adj usted to reflect the fact that spills or items falling off forklifts do occur within the egress route. 1he code addresses these short -term blockages by requi ring management to have a plan and pro cedu res in place to manage and remedy the occurrence so that the blockage is not viewed as a per se violation of the code. Where the exit and path of travel are not clearly visible, signs must be provided to indicate the direction. A short common path of travel to two otherwise remote exits is permitted, except from an area of high hazard . Exit access must not pass through areas of high hazard. '" ' hen evacuation must be delayed because of the need to shut down an operat ion safely or for any other reaso n, the additional provisions governing ancillary facilities contained in NFPA 101® must be met. Remember to ensure that all elements composing the means of egress remain in compliance with the requirements during periods of renovation and construction. TI1is is especially important when partitions are erected to separate construction areas from work or production areas. Large loss fires have occurred in all types of occupancies during periods of construction, and indu str ial occupancies are particularl) ' vulnerable because of their comp lexity and the work processes performed in them. Emergency lighting is required in all facilities except those occupied only during daylight hours in which skylights or windows are arranged to provide, during those 519

SECTION 3: Occupancies

hours, the required level of illumination for all portions of the means of egress. Check the type of lighting used and review records of servicing and testing. If battery packs are used for an emergency power supply, there shou ld be an indicator light to show fullcharge condition and a test button to check its operability. Youmust also be aware that the industrial occupancy chapter of NFPA JOI® (Chapter 40) contains requirements for equipment walkways, platforms, ramps, and stairs that differ from the baseline dime nsional criter ia of Chapter 7 ofNFPA 101®.

Protection of Openings When inspecting industrial o cupancies, d1eck !he integrily of fire barrier walls and fire-rated floor-ceiling and roof-ceiling assemblies. With changing technology, changing operations and processes, and new tenants, industrial plants undergo revisions that create openings and holes through fire-rated assemblles. Pipes, electrial cond uits, cable trays, and other penetrati 11 g items must b' properly ealcd and protected. Penetration seals must be made of approved or listed materials and be installed in such a way that they maintain the fire rating of the wall or floor assembly in which they are installed. Ductwork going through fire-rated asse1nblies must be equipped with fire dampers unless specifically exempted by code. \i\lhere dampers are prohibited, such as for exhaust systems for cooking appliances, such ductwork must not pass through rated assemblies or must be properly enclosed. Inspectors shou ld check to see that fire doors are of the proper rating for the enclosure in which they are installed and that they are self-closing and positive catching. They should also check that automatic closme devices and mechanisms operate properly. Any obstructions that could interfere with the fire door closing completely must be removed (e.g., wooden wedges or the door being tied open). Examine the tracks of vertical sliding and roll-up doors for mechanical damage, especially when the openings are used by industrial trucks . Consideration should be given to installing guards to prevent stock from being piled up against the door or vehicles from striking it. Make sure that all doors get closed at the end of the business day, and inspect each door for evidence of excessive wear and tear, modifications to the door, or other defects that make its continued use suspect. Maintenance and testing of these doors should be done in accordance with NFPA 80, Standardfor FireDoors and Other Ope11i11g Protecti11es. You should check all vertical openings, such as convqors, elevators, stairs, dumbwaiters, and refuse chutes, for proper enclosure and to be sure that all openings are properly protected and of the prop er fire rating. Also check that pipe chases and other vertical recesses are firestopped. Ensure that fire shutters have proper automatic closing devices and that such mechanisms are operable. On building exteriors facing fire exposure hazards, doors and windows should be checked for the proper rating and glazing. The glazing of all fire doors that are permitted to have glass should also be examined to ensure that the glazing is of the proper size and thickness and instaUed properly in acceptable frames. 520

CHAPTER41: IndustrialOccupancies

Haza rdous Materials You must determine the properties of all of the materials used in industrial plants and see that they are store d and handled safely. To do this, especial !}' with chemicals, you must have good reference sources. Because inspe ction is not an emergency activity, you can reco rd what is found , how it is stored and handled, and then do additional research . lf the research indicates that special precautions are required, you will need to perform a follow-up inspe ction to ensure that such pre autions arc bei11gtaken. Use ca ution, because the handling of the materia l- for exc1111ple, the handling offlammab le liqu ids that release vapors-can pose a sign ifica nt potential for a hazard and sho uld be corrected immediately. Once a material has been identified, classified, and categorized by the degree of its ph)'Sical and chemica l properties, half the work has been done. You must then determine whether there are excessive amount s of materials for the fire area and for the provided level of protection . You must also determine the requirements for and the adequacy of the venting, if provided; whether electrical equ ipment has been classified properly; whether electrica l wir ing is in good condition and properly maintained; and whether the re are ignition sources. Production and process areas should contain only those amounts of hazardous materials that are necessary to the immediate process or operation. 1he maximum amount should be limited to the 11eeds of one day or one shift, and then only when relatively small amounts are used. Inspectors must be sure to inspect the methods used to I ransfer hazardous materials from the shipping con tainer or bulk storage area into the pro cess or operation area. 1l1ey should also look for possible ignition sources . l\ifany hazardous industrial processes have been fully evaluated, and standards have been established for their safe operation. 1l1e Nntio,wl Fire Codes® conta in all of the codes and standards for safe operation of the most common industria l processes and many that are not common . In addition, the National Fire Protection Association (NFPA) Fire ProtectionHn11dbookcovers a broad range of fire hazards that are found in major industrial occupancies. NFPA 400, Hnznrdo11sMnterinls Code consolidates aU the fire and life-safely requireme nts applicab le to handling, storage, and use of hazardous materials into one single comprehensive resource and offers detailed criteria to help with your eva luation. Inspectors should use this material when evaluating hazardous industria l processes and also when conducting inspect ions. In situations in which there is no established standard to follow, inspectors mu st use their judgment in identifying the process or operational hazards and determ ining whether they are being controlled properly. The protect ion afforded must be appropriate to the hazard or hazards, and ignition sources must be controlled. A relatively small hazardous process incidenta l to the main operations, such as a small paint spray booth, should not change the classification of the entire area to one of high hazard. lnspectors should look for the insta llation of a special exti nguishi ng system, such as ca rbon dioxide or dr) ' chemical, because very often it is required by a standard to provide protection of the process. They ma)' also find that the installation of draft curtains or special venting arrangements are required.

521

SECTION 3: Occupancies

In the chemica l and allied industries, there are hundred s of different pro cesses and thousands of var iations that may be be)'Ond you r ability to evaluate. This is not to say that inspectors shou ld skip inspect ing these premises or give them only a superficial inspect ion . Inspectors should identify all of the chem icals used and their hazardous properties, and they should then place them in broad classifications, such as corrosive, flammable, combustible, unstable, or react ive, based on the degree of hazard. You shou ld ask to see a copy of the Material Safety Data Sheet (MSDS). An MSDS is provided by the ma nufa cturer, compo und er, or blende r of the chemica l and conta ins information about the chemica l compos ition, physical and chemical properties, health and safety hazards, eme rgenq 1 response , and waste disposa l of the mater ial. Evaluating storage, transfer m ethod, compatibility, and so on can give you a good indication of whether safe practices are being followed. Some general ques tions concern ing the various processes can be asked: • Is th ere an operato r's manua l? • Is the operator traine d? , Does the manua l cover the hazards of the mater ials, the safe and critica l tem pera tu res and pressures, the proper sequence for add ing materials, and the consequences for failure to follow a formula exactly? • Does the pro cess have fail-safe au tom atic con trols? Asking many additional questions ca n help yon make a limited evaluation. To obtain meanin gfu l information, inspe ctors must gain th e co nfidenc e of managemen t and show that the y can be trusted with trade sec rets and confide nt ial inform at ion. Because there are trade secrets in every pha se of indus try, inspectors sho uld not be ins ulted if they are asked to sign a pledge of confi dentiality.

Storage Outdoor Storage. The storage of materials outdoors usually is limited to those used in large quantiti es and tho se that are not susceptible to damag e by weather. Storage pra ctices should follow recommended safe practices. All outdoor stora ge should be arrange d so that it will not interfere with firefight ing access to and around buildings and to the storage itself. If the stored materials are com bus tible, ignitable, or both, they should be far enough away from other buildin gs so that if on fire, one will not be an exposur e hazard to another. 'l11ere should be sufficient fire hydrants and hose houses with fire lane s to make outdoor combustib le storage access ible on all sides . Areas must be free of vegetation and other loose combu stibles. Indoor Genera l Storage . Preferably, storage areas shou ld be in separate buildings or in cut -off sec tion s of buildings used for no other purpose. If storage is incide ntal to the main use o f the building , inspectors should st ill follow the general ru les for storage occupancies as much as possible, but they must also .make additional judgmen ts as to safe p rac tices. Haza rdou s materials in relatively small amou nts shou ld be stored with due regard for their hazardous properties: flammable liquid s shoul d be stored inside cut-off storage rooms or cabinets; loo se, high ly

522

CHAPTER 41: Industria l Occupancies

combus tible fibers should be stored in metal or metal -lined bins with automatic closing covers; and pyrox1'lin plastics should be stored in vaults and tote boxes. Many of these mater ials have speci fic standards that address the proper storage applications . You must be certain that piles are stable and separate d by adequate aisles, that clearance to sprinklers is maintained , and that materials being stored are compatible. Stock piled over 12 ft (3.7 m) in height and rack storage of material require special considerations. See NFPA 13, Standardjt1rthe Jnstnllntivnof Sprinkler Systems, for proper methods of storage and protection . Idle pallets awaiting reuse, repair, or disposal can be a constant problem. 'fl1ey should never be stored in unspr inklered areas. When they are stored in sprinklered areas, the piles should cover a small area and be less than 8 ft (2.4 m) high . They should preferably be stored outdoors, well away from buildings and other storage areas. Housekeeping and Maintenance. Poor housekeeping and maintenance practices can be the most frustrating problem you will encounter and are probably the principal reasons for follow-up inspections. Improper housekeeping is not onl>' a fire hazard, but it also indicates a lack of management commitment. Improper storage of materials and poor maintenance of pumps, piping, and exhaust systems can make floors slippery and atmospheres dusty and can interfere with the proper operation of fire protection equipment. Industrial occupancies with good housekeeping and maintenance practices are relatively easy to inspect. As a general rule, where housekeeping and maintenance are a priority, most items of fire safety and protection will also be good, and less time will probably be needed to make a thorough inspection. You should see that waste is removed properly and disposed of safely. Where waste has value as salvage, a safe collection area should be set apart and maintained in an orderly way. Chemical wastes must be disposed of in a manner that is safe for the envi ronment and in accordance with state and federal regulations. Control and mitigation of dust explosion hazards are also of concern in many types of industrial occupancies. Cutting, milling and processing operations can generate fine particulate materials that are prone to settle on equipment surfaces as well as on the buildings, structural and architectural components . Chapter 44 of this text covers the various environment and protection measures necessary to manage a range of operations that may cause a dust explosion hazard.

FIREPROTECTION vVhen inspecting industrial plants, you must be certain that existing fire protection

systems and equipment are properly maintained and that portable fire extinguishers are properly located and are accessibl e. The locking pin should be in place and sealed, free from damage . TI1ere should be no foreign materials in hoses and nozzles that would interfere with their operation. Pressure gauges on extinguishers should indicate they are ready for use. Examine the tag for the last inspection and hydrostatic test dates. Extinguishers should be in cabinets or have covers when they are located in dusty or corrosive atmospheres. Their location should be clearly marked. TI1e discussion on 523

SECTION 3:

Occup~ncies

automatic sprinkler and other water-based fire protection systems elsewhere in this text addresses the requirements for the inspection, testing, and maintenance of waterbased fire protection systems snch as automatic sprinklers.

Water Supplies and Fire Pumps Inspectors will have to rely on records and reports when inspecting water supplies, because much of the piping and valves is buri ed. Industrial occupancies often have more than one source of water supply (e.g., tanks, ponds , and city connections), and each one will need lo be examined . Inspectors should check aboveground portions for proper maintenance. They shou ld make sure that all Sllpply valves are open, gravit)' tanks work, fire hydrants are maintained, and so on. They should review records of water-flow tests, pump tests, valve-operating records for underground valves, and hydrant inspectio n reports. Signs of neglected maintenance will usually be obvious. You should check pump rooms to determin whether fire pumps and fire booster pumps are read)' for operation if they are needed. TI1epower should be on al the controller ofelectricallydriven pumps, no trouble lights should be on, and the jockey pump should not run excessively or kick on too often. The fuel tanks of interna l combust ion drivers should be foll or nearly so, and batteries should be fully charged with a trickle charger to keep them charged. Review records of pump testing and maintenanc e.

Sprinkler Systems If sprink ler systems are to pel'form as they were intended to, periodic inspection and maintenance are essential. Inspect them visually and witness periodic tests. In general, hands-on testing should be the responsibility of the building owner or an authorized maintenance company.

Special ExtinguishingSystems Special extinguishing systems can consist of Halon 1301 (mostly on older systems), dean agent, carbon dioxide, dry chemical, and foam systems. Inspectors must have a· good idea of how the various systems operate. The inspection must be visual; the valves should not be tested or manipulated. Inspectors shou ld check that the extinguishing agent used is suitable for the hazard(s) being protected and that a reserve supply is available, if required. TI1eyshould check that actuating devices and alarms are operational, see that nozzles are dear and free of foreign matter, and determine that nozzle caps, where used, are free. Nozzles should be properly aimed and protected from damage. \,Vben systems are of the total flooding t-ype, all openings required to be closed on system actuation should be checked for proper operation. It is important that the hazard enclosure be properly scaled before system discharge. Piping, cable assemblies, valves, and manifolds should be checked for damage. Records of inspection, testing, and recharging should be examined to determine whether maintenance has been proper. Specificinformation on these systems can be found in the appropriate standard or code in the Nntional Fire Codes®. 524

CHAPTER 41: Industrial Occupancies

Standpipe Hos Systems Jn industrial occupancies, standpipes and hose stations are more often supplied from the sprinkler system than from a separate system. Therefore, inspectors shou ld inspect these systems as the)' would sprinkler systems. They should check that all valves on the waler supply are open and that the fire department connection is accessible. Threads should not be damaged and should be properly capped . Swivelsshould work freely, and threads should be compat ible with those of the local fire department. Inspectors shou ld check hose cabinets or reels for proper installation, location, and accessibilit)'-They should check the hose for signs of deterioration or need for rerack ing, and they should be sure that the attached nozzle works frcdy. Hoses and outlets should have the same threads as those of the local fire department, or there should be an adapter in the cabine t or at the reel.

Fire Alarm Systems TI1einspection of an alarm system should be visual. Testing should be the responsib ility of thorough!)' train ed employees or an outside alarm service company; however, )'Oil should review these test records as part of )'Our inspection and should observe alarm -initiating devices for proper location , mechanical or electrical damage, painting, loading, or damage caused by a corrosive atmosphere. Wiring should be in good condition and secure ly fastened. Control panels should be in a safe location and readily accessible. The "power on" light should be Iii, and all trouble lighls and signals should be off. Service and test records should be in the panel enclosure. When emergency power is required, batteries should be fully charged. Equipment should be free from dirt or grit that can find its way into delicate part s and contacts. Manual fire alarm stations should also be inspected for signs of any problems. Wiring should be secure and in good conditio n, and there should be no tape, wire, stri ng, or other enc umbrance to the effective use of the system. TI1estations should be located near the exits along natural egress palhs. You should check audible devices to see whether they have been tampered with, painted, or dam aged ,ind whether they can be heard above the ambienl noise. Also check all records to determine that required servicing and testing h,ive been done, and review records of all supervisory signal systems and alarm signal S)1Stems. Detection systems for actuating special extinguishing systems are usually serviced by an outside service company under con tract.

BlBLIOGRAPHY Cote, A. E., NFPA FireProtectio11Hn11d/Jook , 20th ed., NFPA, Quincy, MA, 2008. NFPACodes,Standards, and RecommendedPractices See the latest version of the NFPA Catalog for availability of current editions of the following documents.

NFPA 13, Standardfor tile lllstnllatio11 of Sprinkler Systems NFPA 30, Flm111nnble mid Co111/J11s tible Liquids Corle 525

SECTION3: Occupancies

Nf-PA 30B, Codefor the i'vlm11ifnct11re n11dStomge o_{AerosolProducts N FPA 32, Stm1dardfor D1yclen11i11g Plants NFPA 35, Standardfor the Mam,Jact11re of Orgn11ic Contings NFPA 36, Sta11dard for Solvent Extmction Plants NFPA 61, Standardfor the Preve11tio11 of Fires and D11stE.\plosionsi11Agricultuml and FoodProcessi11g Facilities NFPA 80, Standardfor FireDoorsa11dOther Openi11g Protectives NFPA 88B, Sta11dnrdforRepair Gamges NFPA JOJ®, L(fe Safety Code® NFPA 120, Sta11dardforCoal Prepamtio11 Plants NFPA 400, Haz1mlo11s MMerialsCode NFPA 484, Standard for Combustible Ivietals NFPA 505, Fire Safety Standardfor PoweredI11dustria/Tntcks Jnc/11di11g Type Desig11atio11s,Areas of Use,Mai11te11a11ce, a11dOpemtions NFPA 654, Sfall(fardfor Ifie Prel'ention of Fire a11d011stExplosions i11the Chemical, Dye, Plwrmace11tical,and PlnsticsIndustries NFPA 664, Standardfor the Prevention of Firesn11dExplosionsi11WoodProcessi11gand Wood111orki11g Facilities NFPA 1124, Codefor the 1vfnmifac/11re, Tm11sportatio11, and Stomge of Fireworks

526

CHAPTER

42 STORAGEOCCUPANCIES Ioseph Versteeg

NFPA 101®, L!fe Safely Code, defines storage occupancies as building s or structures used to store or shelter goods, merchandise, products, vehicles, or animals. Examples are warehouses, freight terminals, parking garages, aircraft storage hangars, grain elevators, barns, and stables. These facilities may be separate and distinct facilities or part of a multiple-use occupancy. \A/hen storage is inciden tal to the main use of the struc ture, it should be classified as part of the main occupancy when determining life-safety requirements. Considerable judgment must be exercised when determining whether storage is incidental to the main use of the building . One consideration is the hazard classification of the contents stored in the area. If they are classified as high ha zard, the room or space must be separated from the rest of the occupa ncy by fire-resistive construction tha t meets the requirements ofNFPA 101@, the local building code, or fire prevention code. In cases where the hazard is severe, both fire-resistive construction and au tomatic fire supp ressio n might be required. You should be aware that storage occupancies or areas of storage occupancies that are used for packaging, labeling, sorting, specia l handling, or other operations that require an occupant load greater than that normally contemplated for storage must be classified as indu st rial occupancies when determining life-safety requirements. Parking garages, whether dosed or open, abovegro und or below, must also be classified as indust rial occupancies if they contain an area in which repair operatio ns are conducted. If the parking and repair sections are separa ted by 2-hour fire-rated construct ion, they can be treated separately. Make sure you know the special requirements for under ground and windowless structures, which are covered in Chapter 11 ofNFPA JOI®.

OCCUPANCY CHARACT RIS ICS Storage occupancies ca n be classified as low, ordinary, or high hazard or a combination of these where mLxed commod ities are stor ed together . Where different degrees of hazard exist in the same stru cture and cannot be separated effectively, the requirements

SEC ION 3: Occupancies

for t!1e most hazardous classificat ion govern. The authority having jurisdiction must use sou nd judgm ent when apµlying this prin ciple of haz ard classification. NFPA 101@ uses the ordinary hazard classification as the basis for general requirem ents. Most storage occ 11pancies fall into this classification, although an incr easi ng percentage are being classified as high hazard because of the rapid fire and smoke development that can be expected in some situa tions. \'\'h en look ing at the overall fire hazard, inspec tors shou ld also consider building construction. Combustible building materia l.s can affect the pread and development of fire, esµecia lly if there are combustible concea led spaces . Co mb11stible insulation is a particular problem in certain storage facilities and represent s a ser ious fire problem. Inspectors must determine specifically the type of any insulation present. i\fodern developments in materials hand ling have brought rapid changes to storage occ upancie s, including high -rack storage areas that can reach heights of 50 to I 00 ft (15 to 30 rn). Computer-con trolled slacker cranes and robot-controlled material handlers are now being used to move materials . Regio nal distribution cen ters that cover severa l acres, which might contain two - or three-level mezzanines, are now being developed. Ministorage complexes that consist of rental spaces ranging from 40 to 400 ft2{3.71 to 37.2 m2) in size are also be ing developed. TI1ese complexes, which consist or as many as 50 to many hundreds of rental spaces in one building, often contain var) 1ing types and amounts of hazardous storage in one or more of the renta l areas and can be located in mu ltiple story bu ildin gs. Storage occupancies can house raw materials, finished products, or goods in an intermediate stage of produc tion, and these materials can be in bu lk form, solid piles, palletized piles, or storage racks. TI1erefore, inspectors should remember that the storage arrangement can great I)' affect fire behavior.

IN SPEC IN G TH

PR MISES

Contents In de term ining life-safety feature s and requirements in a storage occupancy, you must first determin e the hazard classification of the contents. Fire behavior will depend on the ease of ignition, rate of fire spread, and rate of heat release of the product itself. Products, however, are often complex items whose fuel content , arrangemen t, shape, and form affect their performance in a fire. A packaged product must be considered as a whole, because that is the way it burns, so in classifying the contents, examine the product, product con tainer, and packaging materia l used. Increasing amounts of pla st ics are now being used as part of the product and as part of the packagi ng. Bicycles have traditionally been all metal except for the tires, but now th e frame and wheels of a bicycle may conta in 50% or mor e synthetic mate rial. Electrical and plumbing supp lies have traditiona lly been meta l, but now many of these supplies, including pip e, conduit, fittings, and junction boxes, are made of plastic. Was hing machines typically have a limited amount of combus tible pa rts in the machine assemb ly; however , today's typical packagi ng arrangement, the machine 528

CHAPTER 42:

Storage Occupancies

packed in a cardboard box surrounded with plastic foam, has made this commodity more hazardous even though the base commodity has not changed. You should become familiar with National Fire Protection Association (NFPA) standards detaiJing requirements for the proper storage arrangement and level of protection for storage of specific items including flammable and combustible liquids, hanging garments, rolled paper, tires, and aerosol containers .

Occupant Load A small number of people in relation to the total floor area will usually be present in a storage occupancy at any one time. Work patterns usually require employees to move throughout the structure using industrial trucks to position the commodity. In totally computerized warehouses, even fewer occupants are present, which reduces the likelihood of early fire detection and the personnel available to begin first aid firefighting operation s. Becaus e of this, NFPA IOI ® has no occupant load requirement s for stora ge facilities. When establishing the occupant load for new and existing storage structures, the authority having jurisdiction will have to obtain in writing (from the building owner or occupant) the actual number of occupants expected in each occupied space, floor, or building. TI1eauthority having jurisdiction must then designate the number of occupants to be accommodated on every floor and in each room or space. Be aware of areas within the building having more concentrated occupant loads such as areas used for packaging, labeling, and sorting. Such areas, because of their small size and functions that support the primary storage function of the building, are considered an incidental industrial use area and now have a calculated occupant load based on 100 ft2 (9.3 1112)per person. Special attention needs to be given to parking garages, which, at given times, could be occupied by many people, such as at the end of a workday or when an entertainment event is over. It should be noted that because of the typical low density of a storage occupancy, egress capacity is rarely a problem if the minimum number and size of exits along with maximum travel distance limitations are met.

MEANS OF EGRESS At least two separate means of egress, as remote from each other as possible, must be available from every floor in a storage structure. In smaller buildings, a single exit is permitted, as long as the common path of travel limitations is not exceeded. Inspect the exit access from within the building, the exit locations, and the arrangement of the exit discharge from the exit to a public way or street (see Chapter 22, Means of Egress). Periodically, the storage arrangements in storage occupancies are modified to keep up with new technology and operations, and these modifications can significantly affect the components of the building's means of egress. Without proper planning, exits can become blocked by storage or rack systems, travel distances significantly increased, dead -end corridors or aisles created, and even exit discharge adversely affected by building additions, altered security measures, or changes to property lines. 529

SECTION3: Occupancies

Exit Access and Travel Di tances All paths of travel from any part of the building must allow the occupants to travel safely, without obstru ctions, to the exits. TI1e travel dista nces to the exit locations are shown in TABLE 42·1. When repair operations are conducted within a parking garage, travel distances must meet the requir ements for the industrial section (Chapter 40) of NFPA 101®. If the repair operat ion area is separated by 2-hou r fire-resistive constru ct ion, the industrial requirements will apply to on ly the part that is used for repair operatio ns. Any rearrangem ent of the storage aisles or add itions or changes to the rack systems made since the occupancy's la t inspection can greally aflect travel distances Lo exit . '" ' hen new mezzanin e levels are added for add itional storage space, check that travel distances to exits are correc t and that the appropriate number and arrangem ent of spri nklers have been added to the new area. When determining exit access, look for ar as where de.:id end or ommon path of travel are created by the storage arrangement. There is no limit to either in occu pancies with a low-hazard classification. In new or existing storage occupan cies with

Maximum Travel Distance to Exits

Low Haz ard Storage Occupancy

Ordinary Hazard Storage Occupancy

High Hazard Storage Occupanc y

ft

m

ft

m

Pmtected throughout by an approved, supervised automat ic sprinkler system in accordance with 9.7.l. I (I)

NL

400

122

100

30

Not protected througho ut by an approved , supervised automa tic sprinkler system in accorda nce with 9.7.1.1(1)

NL

200

61

75

23

Flammable and combustible NA liqu id produc ts stored and protected in accordan ce with NFPA30, Flommobleand

NA

NA

150

46

Level of Protection

CombustibleLiquidsCode NL: Not limit d. NA:Not applicable. Source:NFPA 10/® , 2012,Table42.2.6.

530

CHAPTER 42: Storage Occupancies

an ordinary-hazard classification, a dead end or common path of travel of up to 50 ft (15 m) is allowed and up to 100 ft (30 m) is allowed if the building is protected by an automatic sprinkler system. No dead-end conditions are allowed in areas that are classified as high hazard except for very small spaces that: • Are not over 200 ft2 ( I 8.6 m2), • Occupant load does not exceed 3 persons . • The travel distance to the room door does not exceed 25 feet (7620 111111) . In parking garages , a dead end or common path of travel of up to 50 ft (15 m) is allowed.

Exits and Locations At least two means of egress are required from all floors and areas of the building in storage occupancies classified as ordinary and high hazard, and they must be located so that a per son can reach an exit location within the allowable travel distan ces. There are several exit requirements for any enclosed parking garage in which gasoline pumps are present. Travel away from the pumps in any direction should lead to an exit, and there must be no dead ends where people could be trapped by a fire originating at the pumps. TI1e exits must lead to the outside of the building at the same level as the pumps or they must lead to stairs . Any story below the one housing the pumps must have exits directly to the outside b)' means of outside stairs or doors at ground level. In aircraft storage and servicing areas, there must be exits at intervals of every 150 ft (45 m) on exterior walls of the hangar and every 100 ft (30 m) along interior fire walls when these walls serve as horizontal exits. TI1e travel distance to reach the nearest exit from any point from a mezzanine t1oor located in an aircraft storage or servicing area must not exceed 75 ft (23 m), Such exits must lead directly to an enclosed stairwell discharging directly to the exterior, to a suitable cut-off area, or to outside stairs . In grain or other bulk storage elevators, there should be two means of egress from all working levels of the head house. One must be stairs to the ground that are enclosed by a dust -resistant I -hour fire -resistive enclosure. TI1e second means of egress can be exterior stairs or a basket ladder -type fire escape that is accessible from all working levels of the head house and provides access either to ground level or to the top of an adjoining structure that provides a continuous path to another exterior stairway or basket ladder -type fire escape leading to the ground level. TI1e underground spaces of an elevator must have at least two means of egress, one of which can be a ladder. You should check all doors that serve as a required means of egress and are identi fied as exits for free and unobstructed operation to ensure that these doors are kept unlocked when the building is occupied. If locks requiring use of a key for operation from the inside of the building are used, make sure that a readily visible sign is posted

531

SECTION3: Occupancies

next to the door on the egress side of the door stating, "This door to remain unlocked when the building is occupied:' 'Tl,elocking device should be readily distinguishable iflocked. J\'1akesure that exit doors located in a high -hazard area swing in the direction of exit travel. In areas where flammable vapors or gases are present, or the possibility of an expl.osion exists, make sure that exit doors are equipped with panic hardware. In ordinary and low-hazard areas that are protected throughout by an approved, supervised, automatic fire alarm or automatic sprinkler S}1Stem, ex.it doors can be equipped with approved, listed, special locking devices that meet the requirements of Chapter 7 ofNFPA 101®. NFPA 101® perm ii horizontal J iding doors to be part of a means of egress. fl also permits the use of a horizontal exit or smoke barrier. There are, however, special requirements in Chapter 7 ofNFPA 101®. It is quite common to find horizontcllexits in storage occupancies due to the use of fire walls or barriers for compartme ntation purposes. When the horizontal exit doorway is prate ted by a fire loor on each side of the wall, one door must be swinging, and the other can be an automatic-sliding fire door complying with specific requirements involving fusible.links(as detailed in Chapter 42 ofNFPA 101®) that must be kept open when the building is occupied. In parking garages, the opening for the passage of automobiles can serve as an exit from the street floor, provided that no door or shutter is instcllledin the opening. In storage areas that contain ordinary- or low-hazard contents and have an occupant load of not more than 10 people, exit doors that are not side-hinged swinging are permitted.

Exit Discharge You must determine that there is a continuous path of travel from the building exit to a public way and that there is nothing in front of the exit door tlrnt would prevent it from working. Also make sure the path of travel from exits opening into an alley leads lo the public way, is well marked, and is illuminated.

Identificat ion of Exit s All required exits and paths of travel to an exit must be identified properly by signs that are readily vlsible from any direction of exit access. Where the exit or the way to reach it is not visible to the occupants, the path of trnvel should be mclrked so that no point in the route is more than 100 ft (30 m) from the nearest visible sign. In large warehouses with high storage, exit identification can be a problem; therefore, you might want to suggest that exit signs be of sufficie nt size for visibility or that the travel paths to exits be painted on the floor. Ensure that exit access routes are illuminated to allow the occupants to exit the building safely. If natural light is not available during the fire when the building is occupied, the il.lumination must be continuous when the buil.ding is occupied. Emergency lighting is required in storage occupancies that are occupied at night or that do not have exterior openings that would provide the required illumination during daylight hours. Check that emergency lighting operates when the norma l lighting circuits for 532

CHAPTER 42: Stor,1geOccupancies

the affected area are turned off When a generator is used to power emergency Iighting, the generator should transfer power and should operate emergenC)' lighting within IO seconds. Check the records and, if possible, be present for a generator lest to be sure it runs properly. When checking battery-µowered lighting units, look for acid corrosion and check the water level of wet-cell batteries and that the unit is fully charged and operational.

Protection of Openings You should check that fire doors operate properly, that they close liglitly, and that the self-closing devices work. Assess the general condition of the doors for obvious damage. Nothing that would prevent counterbala nce closing hardware from operating freely should be stored around the fire doors, and nothing should block the doors open. You should check lhal all door hardware and closillg devices are lubricated and move freely, and examine all fusible links associated with the closing hardware to see that they are positioned proper!)' and have not been painted or wired together. Jt is important to carefully check materials-handling conveyor systems that pass through fire walls. ls there any air-handling ductwork µassing through fire walls? NFPA 90A, Standardfor tire Tnstnl/ntionof Air-Co11ditiolli11g and \lentilntingSystems, requires any ductwork passing through a 2-hour fire wall to be protected by fire dampers. Check that all openings through the walls made for electrical cables or conduits are tightly sealed with a material that affords the same fire-resistance rating as the fire barrier. vVhere storage buildings are susceptible to exterior exposure problems, you shou ld check that fire shutters are operational and that wired-glass windows are properly placed. All wired glass that is missing or cracked should be replaced. Verify that installed roof vents are operating properly and that snow is not allowed to accumulate on the vent hatches during the winter.

GENERALSTORAGE PRACTICES Indoor NFPA l, Fire Code, defines commodit)' storage as both pile and rack storage and describes four classes of ordinary commodities and three classes of plastics according to how easily automatic sprinklers will control a fire in them. Reier to this code to determi ne the proper storage arrangement in bu ildings protected by automatic sprinkler systems. You should make sure that materials that could be hazardous in combination are stored so they cannot come in contact with each other, and verify that safe loads for floors and rack storage units are not exceeded. Floor loads for water-absorbent materials should be reduced to account for the added weight of water absorption during a fire. Check the clearance of stored material from sprinklers, heat ducts, unit heaters, duct furnaces, flues, radiant space heaters, and lighting fixtures. TI1ewall aisle space should be at least 24 in. (61 cm) in storage areas where materials that will expand with absorption of water are stored. Verify that aisles are maintained to keep fire from spreading 533

SECTION3: Occupancies

from one pile to another and to permit access for firefighting, salvag e, and removal or storage . Also verify tha t all automa tic sprinkler co nt rol valves, hose stations, and por table fire ex tinguishers are access ible and th at there is free access to all fire protection equipment. All unused wood or plastic pallets should be kept outside and stored in stacks no higher than 15 ft (4.6 m). Idle pallets are permitted to be stored inside the building when it is protected with an automat ic sprin kler system. During th e i.nspection, you shou ld check to see whether exterior access door s and windows are being blo cked with storage that would affect firefig hting operations and prevent access into the bu ildin g.

utdoor Con firm tha t storage pile s are no t stacked too high and are in stable condi tio n and that a isles are sufficient ly maintained between individual piles, between piles and buildings, and between pil es and bou ndary lin es of th e stora ge site. Also note whether th e enti re properly is enclos ed with a fence or some other means of keeping unauthorized persons from entering . There sho uld be a gate to allow fire department apparatus to enter the area in the event of a fire. TI1e storage yard should be free of tmnecessar) ' combustible material s, weeds, and grass, and any tarpaulins used to cover materials should be made of fire -retardant fabric.

HAZARDOUS MATERIALS Ma ny different materials with different hazards can be stored in a storage occupancy, or the entire occupanC}' can be used to store a spec ific hazardou s material. Special requirements for the storage of hazardous materials are found in several documents within the National Fire Codes®. You should be able to reco gn ize out -of-the -ord inary storage and refer to th e appropriate code or standard to det er mine special storage arrangements and protection requi rements . Examples of hazardous material s in clude rubber tires, plastic products, combustible fibers, pap er and paper products, h anging garments, carpet ing, pesticides, flammable liquids and gases, reactive chemicals, and flammable aernso .1containers. Storage of aerosol containers should me et the requirements of NFPA 30B, Code for the Mamfac/11re and Storage cf Aernsol Products. All stora ge occupancies should be for proper ly iden tified on the outside of the building using NFPA 704, Standard Syste111

the lde11t(ficntio11 of the Hazards of lv!nterialsfor EmergencyResponse.

Industrial Trucks Deter mine that the indu stria l trucks being used a rc approved for use within the building for th e ha zard of the materials being stored. NFPA 505, Fire Safety Standard

for Powered Jnd11strialTrucks b1cludingType Designations, Arens of Use, Conversions, 1\1ai11te 11a11 ce, and Opernlio11s, designates the types oftrncks that ca n be used in hazardous areas. A fire extinguisher that can be used on flammable liquid and electrical fires should be mount ed on each trn ck. Confirm that the trucks are be ing maintained, that all refue ling operation s are conducted outside the bui lding , and that fuel for th e trncks 534

CHAPTER 42 : Storage Occupancies

is properly stored . Examine the area where batteries are recharged for electrical trucks. Areas used for the repair of trncks should be separated from the storage area.

Hazardous Processes You should assess the precautions management takes when a welding or cutting operation occurs in the storage area. In some cases, these operations should not be allowed at all until the hazardous materials are removed from the area. Dur ing welding operations, all combustible materials located below the operation should be removed or covered with a fire retardant cover. Portable fire extinguishers and small hose lines should be hiid oul ready for operat ion. A fire watch should be presen t at all times during the operation and for at least 30 minutes after the welding or cutting is completed. If fuel pumps arc located in a parking garage, you should check that the dispensing unit and nozzle are approved and that no ignilion somces are located within 20 ft (6 m) of the di pensing area. When the dispensing units are located below grade inside the building, the entire dispens ing area must be protected with approved automatic sprink ler systems. Make sure there is mechanical ventilation for the dispensing area to remove flammable vapors and that the mechanical ventilation system is electrically interlocked with the dispensing unit so that no dispensing can be conducted without the ventilation S)'Slem being in operation.

HOUSEKEEP!NG Look for debris and trash accumulated in out-of-the-way places and neglected corners. The level of fire safety is greatly improved when areas are kept clean and neat. All waste generated daily should be removed from the building and disposed of in a safe manner outside the building. Check for the accumulation of dusl and lint on sprin klers, on fire door self-closing hardware, and around electrical motors and compressors. All containers used for the disposal of waste material must be made of noncombustible materi als and have lids. In grain storage buildings, the single most important fire prevention practice is effective daily removal of dust, which will collect everywhere. Housekeeping in this type of occupancy should be done consistently and carefully. See Chapter 44 of this text for specific criteria concerning opera tions in dust-prod ucing environments .

FIREPROTEC ION Sprinkler Systems A major factor in large fire losses in storage buildings has been the overtaxing of the automat ic sprinkier system or associated water supply,which were improperly designed or became inappropriate for the type of material stored and the storage arrangement. Fire losses have also occurred because the sprinkler system water supply has been shut off. Sprinkler plans should be checked to determine the hazard that the system was designed to protect. During the inspection, check whether the mater ial being stored or

535

SECTION3! Occupancies

the stora ge arrangement has cha nged in a wa}' that would req uire redes ign of the sp rin kler system. Detailed inspectio n records shou ld be kep t indica tin g the type of material store d, pi le ar ran geme nt , aisle width, stora ge method s, and height of storage ma terials. Pay specia l attent ion to buildings protected by older sprinkle r systems des igned for Class II I or lower commo dit ies that now store more hazardous mat erials or have more haz ard ous storag e arrangements. Verify that the spri nkler con trol valves arc accessible, not blocked by storage, and in th e open µosi tion . Also, confirm that lhe S)1Stem ha s been maintained proper!)' , is in working order , and th at all alarms operate wh en tested , properly iden tifying the alarm/ superv isor}' condi tion. ·n, e out side fire depa rt me nt sp rinkl er conne ction must no t be blocked by storage. Look for any areas unprot ected by spri nklers, such as sma ll office euclosures with ceilings, mezzanines, or blind co mbustibl e spaces .

Standpipe H se Sy t ms Hose stations and standp ipe co nnect ions must not be blocked by storage mater ials. TI1ere shoul d be an adequate number of ho se stations, so that all areas of the storage building s can be reached by the hose stream. All hose stat ions sho uld be identified prope r!)'· Assess the condition of the hose and nozzle s and find out wh ether employees are expected to use this equ ipme nt and, if so, whet her they are trained properly for using the stan dp ipe hose system.

Fire Extinguishers You should determine that fire extin guishers are acces ible, that they are the correc t type for the hazard, and tha t their loca tion s are identifi ed . All extinguishers should be full)' charged and inspected at least annu ally. Employees shou ld be trained to use the ex tinguisher correctly.

Fire Pumps Th e fire pump shou ld be exam ined to determ ine wheth er it is being proper ly inspected , teste d and maintained and whether it is being run weekly and tested by a qu alified contractor at least annually. Verify th at all alarms operate when tested, an d properly identify the alarm /supervisor}' condit ion. Determine whether the pump is set for automatic or manua l operation and check that all controls are working. Also deter mine that proper documentation of testin g and maintenance is being maint ained . Chapter 17, Automatic Sprinkler and Oth er Water-Based Fire Protection Systems, ad dr esses the requirements for the inspect ion, test ing, and maintenance of water -based fire pro tec tion systems such as au toma tic sprinkl ers.

Alarm System Because storage buildings are usually large open -floor areas that are occupied by on ly a few employee s who are working in mall)' differen t pa rts of the building, these buildin gs sho uld have a fire alarm system that , when op erate d, will so und an alarm at a

536

CHAPTER 42: Storage Occupancies

continuously attended location so that some type of emergency action can be initiated. Tf the occupancy has a trained industrial fire br igade or an emergency prefire plan, there should be a means of notifying people in all areas of the building so that the fire brigade or action plan can be initiated. NFPA JOJ® requires a fire alarm system in storage buildings when they contain either ordina ry or high -hazard contents and have an aggregate floor area of more than J00,000 ft2 (9300 m2). This requirement would not apply if the occupancy is protected by an automatic extinguishing system. A fire alarm system is also required in public parking garages, except when the parking structure is classified as an open -air structure. When inspecting this type of alarm system, make sure that the entire S)'Slem ao• ship, barge, or other vessel permanently fL,ed to a foundation or mooring or unable to get under way under its own power and occupied for purposes other than navigation . Water-s11rro1111derl structures: Water -surrounded structures are structures completely surrounded b)• water . Me111brn11e structures: Membrane structures are buildings or portions of a building incorporating an air -inflated, air-supported tensioned-membrane,

CHAPTER43: Special Structures and High-RiseBuildings

membrane roof, or membrane-covered rigid frame to protect a habitable or usable space. 10. Tents: Tents are typically erected on a temporary basis and consist of a pliable covering supported by beams, columns. poles. arches. orb}' ropes and/or cables. l l. High-riseb11ildi11gs: High-rise buildings are buildings where the floor of an occupiable stor)' is greater than 75 ft (23 111)above the lowest level of fire department vehicle access. The requirements unique to each of the different t)'pes of special structures identified in Chapter 11 ofNFPA /OJ® are to be applied in addition to the requirements mandated b)' the applicable occupancy chapter. One ex.imple is a bank reccmis-keeping facility located partly in the sub-basement of a new office building and partly on the fourth floor of the same building. The Chapter 38 requirements of N FPA 101® applicable to new business occupancies must be met for both par ts of the facility. Additionall)', the portion in the sub-basement must meet the provisions of Section 11.7 of NFPA JOI® applicable to underground and windowless structure s.

S

UCTU E CHARACTE IS ICS

A typical occupancy in a special struchire will still fall under one of the main occupancy classifications previously discussed. Thus, the means of egress and nre protection requirements for that occupancy apply,as do the additional requirements for the special structure. Examples of typical occupancies in special structures include the following: • A restaurant located in a permanent!)' fixed boat or ship. T11isis clear!)' an assembly occupancy (the occupancy classification). which is located in a ship (the special structure). • A souvenir shop in an earthen bunker or cave. This is a mercantile facility (the occupancy classification) in an earthen enclosure (the special structme). • A hotel supported on pilings along a waterfront that is connected to the mainland by access ramps. T11isis a hotel (the occupancy classification) that is housed on pilings (the special structure). ·when inspecting a special structure, which can be difficult, first determine which general occupancy classification it falls under. TI1enit will be easier to determ ine the structure's special feahires and the requisite applicable portions of Chapter I 1 of NFPA lOJ®. If the special structu re has protection needs not fully addressed by the applicable occupanc}' chapter. use the fundamental provisions given in Chapter 4 of NFPA JOJ® to evaluate the constrai nts the structure's special features place 011 proper!)' protecting the occupants.

SPECIALSTRUCTURES This section explains the unusual conditions inspectors will see and the specific observations that they will have to make when inspecting special structures. T11eyshould use this information in conjunct ion with the information contained in specific occupancy chapler(s) ofNFPA 101® to evaluate the special structure . 539

SECTION 3:

Occupancies

Open Structures Open stru ctures are common i11industrial operations; therefore, most of the tim e the structure will come u11der the guideli nes of those for industrial occupancies. The pri. mary problem will be determining whether the occupa nC)' is a general, spec ial purpose, or high-hazard industrial occupancy. Typically, the high-haza rd industrial occupancy classification will be determined based on the hazard classification of the building's content s and processes. Open -air struc tur es a re classified more commonly a special pmpose industrial occupancies, which are defined in Chap ter 40 of NFPA 101®. Special purpose induslrial occupan cies have a rclalively low density of emp loyees, and much of an oµen-air stru cture is occupied by machinery or equiµment. Typically, the open structure facilitates access to the equipment with plalfonns, grat ings, st.iirs, and ladder s. The structure might even have a roof to provide some proteclion from the elements. It is difficult to delcrmine when a stru ctur e is op en and when it is enclo sed. Many open structures will have some walls that are intended to shie ld the operations from environmenta l conditions or to segrega te operations. 1he authority having jurisdiction must determine if lhe structur e truly meets the definition for open struclures or if the structure is, in fact, a building. To determine whether th e structure reall}' is an open struc tur e, yo u must decide whether it would react as an enclosed building in th e event of a fire. Walls acting in conjunction with a roof enclose lhe combustion proce ss and products of combustion, th ereby allowing th e fire to spread both horizontally and vertically to unaffected areas within the bui ldin g. However, an open structure allows the products of combustion to vent to th e atmosphere instead of spreading lo unaffected areas of the structure. Obvious!)', this is dependent on wind and climatic co nditions, but the overall concep t is valid. Cou ld the walls cause the products of combus tion during a fire to be directed or channeled to other unaffected portions of th e structure, thus preventing Ihem from ven ting to the atmosphere? If the answer to this question is "yes" or "pro bably; · then you mi ght have to consider that portion of the structure as a build ing . Once inspectors have classified the struch1re, they sho uld conduct the inspec tion based on the occupancy classification(s) and the special provisions provided in Chapter 11, Special Structures and High -Rise Buildings, of NFPA JOI®. TI1ere are no special provisions for open -air struc tures, but Chap ter 11 contains several exceptions for th is form of spec ial struc tu re. One of them permits open structures to have a sing le means of egress when they are occupied by no more than three persons and have a travel distance of not more than 200 ft (61 m). A fire that occurs in an open struc h1re usually does not pose as serious a threat to life as does a fire in a building, unless the structure contains high-hazard operations. \,Vhen you are inspecting an open st ruch1re that houses a high -hazard operation, refer to Chapter 40 of NFPA 101® and carefully evaluate the life-safety featur es of the open st ruc tu re. When high -hazard operations are involved, the egress system usually becomes the biggest problem, especially on levels that are above grade. No simple generaliwtions 540

CHAPTER 43: Special Structu res and High -Rise Build ings

can be made about this probl em; therefore, each ind ividua l structure must be evaluated on its own merits and the level of protection being provided.

Piers A pier, as defined by NFPA 307, Stn11dnrd for the Construction n11dFire Protectionof Marine Temrinnls, Piers, nnd Wlinrves,is a structure , usuall y lon ger th an it is wide, that projects from land into a body of water. It can have an open deck or have a super structure. Contrary to its exact definition, piers can be constructed over land. Occasionally , a designer will construct a pier of earth that pushes its way out from the main body ofland into an area that , for elevation reasons , might not be usable o therwise . A building tha t can be classified under one of the other categories covered in NFPA 101® will be erected on this earthen pier. Althou gh th e pier is no t mad e of tradi!'ional structural elements, it is still a pier. The evaluation process require s you to determine the occupancy require ments for the building and then assess the affects the unusu al stru cture, the pier, will have on them . Ma ny times a struct ur e is located within what first appears to be an unu sual circumstance , but it willstill have the typical fire prot ection issues and circumstances ofa building that doesn't have the added feature assoc iated with a special structure . Chapter 3 of NF PA 307 contains requirements for property conserva tion features of piers and wharv es, and Chapter 11 of NF PA 101® also describes piers . An exception to the number of exits required by NFPA JOI® is noted in Section 11.5.2 of Chapter 11: "Piers used exclusively to moor cargo vessels and to store mater ials shall be exempt from mnn ber of means of egress requ irements where prov ided with proper means of egre ss from structures th ereon to the pier and a single mean s of access to the mainland, as appropriate with the pier 's arrangement." Aside from this exception, th e ap propriate occupancy chap ter and any other applicable provision s of Chap ter 11 would apply to piers.

Towers A tower, as defined in Chapter 3 of NFPA 101®, is "an enclosed indep en43·1 A tower. den t structure or portion of a buildin g FIGURE with elevated levels for suppor t of equipment or occupied for observation, control, opera tion, signaling , or similar limited use .... " (FIGURE 43·1).A common misapplication is to 541

SECTION3: Occupancies

apply the requirements for towers to a high-rise building simply because the word tower appears in the building name. Chapter l l of NFPA JO/® contains requirements for towers that are typically used for purposes such as forest fire observation, railroad signaling, industrial purposes, and air traffic control. Typically,they are not occupied or are occupied by a limited number of persons, generally with no or very limited general public access, who are capable of elf-preservation. Usually,there are no provisions for living or sleeping in such towers. \o\1hen inspecting towers that meet the requirements of Chapter 11 ofNFPA ,OJ ® , keep in mind the limited access and use and the nature and character of the specific occupancy involved.If the tower is used as an assembly occupancy or contains more than just a few occupants, il probably does not fall under the requirements of Chapter 11 and should be reviewed wholly under the requirements of the appropriate occupancy chapter. NFPA 101® does not require towers to have any special features for means of egress, but it does provide several exceptions to general requirements for means of egress in Chapter 11, some of which are described brieflr here. 'Ole code permits ladders to be used as a means of egress when the tower is occupied by three or fewer people. TI1ecapacity and width of the means of egress have to provide only for the expected number of persons occupying the tower. (See Chapter 11 of NFPA JO/® for all of the exceptions.) Towers are permitted to have a single exit if the following conditions are met: l. 'TI1etower is occupied by fewer than 25 persons. 2. 1he tower is not used for living or sleeping purpos es. 3. The tower is of Type I, II, or TVconstruction. 4. The tower interior finish is Class A or B. 5. 1he tower has no combustible materials in, under, or in the immediate vicinity, except necessary furniture . 6. There are no high-hazard occupancies in the tower or immediate vicinity. When the tower sits atop a building, additional criteria must be met to satisfy the provisions that permit a single exit from the tower portion of the building. 1l1e average tower will meet these conditions, but some unusual towers, such as the Washington Monument and the Statue of Liberty, might not do so. When deciding whether the single exit provision applies, keep in mind the actual configuration of the tower, the fuel load, the exposure of the tower, and the protection it has. Usually, the use of the single exit provision can still be justified when an overall evaluation is completed. Changes to NFPA JOI® in the l 990s have incorporated egress and protection features unique to air traffic control towers. Among these changes is the allowance to use an elevator, with conditions, as the second means of egress from the tower. During the inspection, )'OU must determine whether the tower is exposed to any combustible materials that might be under or in the immediate vicinity of the structure. The inspector or the authority having jurisdiction should not establish arbitrary requirements that would severely restrict the use of the tower; however, you should ensure that the tower could not be exposed to an exterior fire severe enough to affect the means of egress system before the occupants could evacuate. 542

CHAPTER 43: Special Structuresand High-Rise Buildings

You shouJd also ensure that any high -hazard occupancy located close to a tower will n ol threaten the integrity of the physical structure of the tower and the egress system. Included are not only hazards such as liquefied petroleum gas storage and explosive -prone occupancies, but also possible exposures to vehicles, such as flammabl e liquid tran sport carrie rs.

Limited Access Buildings TI1e hazards of a limited access building are very similar lo those of underground structures. TI1ercfore, the same concerns about underground structures would also relate to limit ed access structures . 1l1e signifi ant 1 ing duels are exposed to weather or moisture, the inspector should examine them carefully to make sure they are moisture -tight. Moisture entering the system can react with dust, which generates heat and serves as a potential source of ignition. 1f the conveying gas- air mixture is relatively wm·m and the dust and collectors are relatively cold, the gas temperature could drop below the dew point, causing moisture to condense. If this is the case, it might be necessary to insul ate the ducts and collec tors or to provide a heating system. Explosion relief for ducts and collectors should always extend to the outside. TI1ey can be provided with anti-flashback swing valves or rupture diaphragms. Fans and housings for fans that are used to move combustibl e solids or vapors should be constructed of cond uctive, nonferrous materials. It is important to note whether dust is drawn through the fan before it enters the final collector . TI1e inspector should also not e whether the fan bearings are equipped with suitable temp era ture-indicating devices wired with an alarm to alert occupants to overheating. TI1e inspector shou ld determine by physical exami nation whether dust or other combustible materials are accumulating in the ducts. If so, this may be the result of inadequate carrying velocity within the du cts.

HANDLING OF SCRAPMETAL Scrap metal may be from both foreign and domestic sources. TI1e material may arrive at the plant site b}' rail, truck, or possibly sh ip or barge. Scrap arriving from some countries may not receive the same level of scrutiny as that from other countrie s. One of the 583

SECTION 4:

Process and Storage Hazard,

concerns with this material is radioactive contamination. Radioactive contamination can occur when instrum entation devices and similar equipmenl containing radioactive isotopes are improperly discarded, ending up in scrap yards. The scrap, if contaminated, can further contam inate the melt furnace, which can shut down plant operatio ns and incur considerable business interruption expense and decontamination expense. vVhen material arrives by truck or rail, it is desirable to use a four-sided fixed scanning system at the entry to the plant to analyze the load for potential radioactive contaminat ion. TI1isis o~en done at the scale house. When material arrives by ship or barge, !he material should be oflloaded in an isolated and secured area where !he material can be scanned as ii is offloaded. Regardl ss of the met hod for receiving the scrap, a se ond scanning is neeli°•J)}a'..EJ

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