SUPPLEMENT 4 Residential Sprinkler Systems John L. Bryan Editor’s Note: Supplement 4 is a reprint of Chapter 10 in the fourth edition of NFPA’s book, Automatic Sprinkler and Standpipe Systems. This material provides a historical perspective of the development of residential sprinklers and standards. This supplement provides details of specific residential fire tests used in the development of the initial residential sprinkler technology and reviews residential sprinkler incentives, tradeoffs, activations, and code adoptions across the United States. This supplement also provides an overview of NFPA residential sprinkler requirements and applications. The first edition of NFPA 13D, Standard for the Installation SPRINKLER SYSTEMS FOR DWELLINGS of Sprinkler Systems in One- and Two-Family Dwellings Fire Death and Injury Data and Manufactured Homes, issued in 1975, exempted cer- tain portions of dwellings from sprinkler coverage based on More than four of every five dwelling fire fatalities (ap- the established fire hazard record. The 1980 13D standard proximately 86 percent between 1986 and 1990) occurred radically changed sprinkler system standards and sprinkler in fires that began in the normal-use areas of a residence: technology by focusing the attention on the ineffectiveness living room, family room, den, kitchen, bedroom, or an of the standard sprinkler for protecting the lives of occu- area typically found in the basement such as laundry or pants in dwellings. For the first time a sprinkler standard heating areas (NFPA 13D, 2002). Karter reported a total required a sprinkler designed to protect the occupant in of 3190 civilian fire deaths in the home in 2004, approxi- the room of fire origin with a fast activation and a unique mately 82 percent of the total civilian fire deaths of 3900 water distribution. The development of the residential individuals.1 The National Fire Protection Association sprinkler resulted in subsequent refinement and improve- classifies ‘‘homes’’ as one- and two-family dwellings and ment of the quick-response sprinkler and the development apartment occupancies. Table S4.1 presents civilian fire of the quick-response extended coverage sprinkler and of deaths and injuries for 2004, with percentage variations the early suppression fast response (ESFR) sprinkler. from 2003. The 1980 edition of NFPA 13D was the first effective Hall2 reviewed the fire incident and loss record for design guide for a residential life safety sprinkler system. manufactured homes for the period from 1980 to 2002. This edition of NFPA 13D brought about changes to NFPA Table S4.2 illustrates the fire incidents, civilian fire deaths, 13 relative to protecting dwellings in occupancies other and injuries with the direct fire loss from manufactured than one- and two-family dwellings and manufactured home fires for the years 1980 to 2002. Table S4.3 compares homes and resulted in the development and issuance of civilian fire deaths and injuries in manufactured homes NFPA 13R, Standard for the Installation of Sprinkler Sys- and conventional one- and two-family dwellings for the tems in Residential Occupancies up to and Including Four years 1999 to 2002. Hall indicated that although the fire Stories in Height, in 1989. NFPA 13R provides a sprinkler incident and fire injury rate is lower in manufactured system designed to protect occupants of low-rise multiple homes, the fire death rate is higher, when examined by the dwelling-unit occupancies. number of housing units, as indicated in Table S4.3. 223 224 Supplement 4 • Residential Sprinkler Systems TABLE S4.1 Estimates of 2004 U.S. Civilian Fire Deaths and Injuries by Property Use Civilian Deaths Civilian Injuries Percent Change Percent Change from Percent of All from Percent of All Property Use Estimate 2002 to 2003 Civilian Deaths Estimate 2002 to 2003 Civilian Injuries 79.3 0.7ם 14,175 82.7 1.9ם Residential (total) 3,225 One- and two-family 58.7 5.0ם 10,500 68.7 2.0מ dwellings1 2,680 17.9 12.3מ 3,200 13.1 24.4ם Apartments 510 2.7 11.8ם 475 0.9 75.0ם Other residential2 35 Nonresidential 7.5 11.5מ structures3 804 63.64* 2.1 1,350 7.3 7.1מ 1,300 13.3 14.3ם Highway vehicles 520 1.1 .0מ 200 0.7 50.0ם Other vehicles5 30 4.8 8.1מ 850 1.2 30.7מ All others6 45 1.4מ 17,785 0.6מ Total 3,900 Note: Estimates are based on data reported to NFPA by fire departments that responded to the 2004 National Fire Experience Survey. Note that most changes were not statistically significant; considerable year-to-year fluctuation is to be expected for many of these totals because of their small size. *Statistically significant at the .05 level. 1Includes manufactured homes. 2Includes hotels and motels, college dormitories, boarding houses, etc. 3Includes public assembly, educational, institutional, store and office, industry, utility, storage, and special structure properties. 4This decrease reflects 100 fire deaths in the Station Nightclub fire in Rhode Island, and 31 deaths in two nursing home fires in Connecticut and Tennessee that occurred in 2003. 5Includes trains, boats, ships, aircraft, farm vehicles, and construction vehicles. 6Includes outside properties with value, as well as brush, rubbish, and other outside locations. Source: Michael J. Karter, Jr., ‘‘United States Fire Loss for 2004,’’ NFPA Journal, Vol. 99, No. 5, 2005, pp. 49. Most fatal dwelling fires occur at night, when people occurred in the kitchen or bedroom. The living room and tend to be asleep. In addition, most victims of dwelling closets accounted for an additional 11 percent of total fires were not in the room of fire origin; fire spread out sprinkler activations. of that room, typically as a result of reaching flashover. Thus, fatal dwelling fires, which account for the largest Dwelling Sprinkler System Standard share of total U.S. fire deaths, pose certain unique opportu- nities and challenges for sprinkler system design. Specifi- In 1973 the NFPA Committee on Automatic Sprinklers cally, a system that covers normal-use areas and prevents appointed a subcommittee to develop a standard for the flashover prevents most fires from reaching the stage at installation of sprinkler systems in one- and two-family which most fatal injuries occur. Many victims are so vulner- dwellings. Basic design objectives for the dwelling sprin- able—not only asleep but often elderly, preschoolers, hand- kler system were to provide: icapped, or impaired by alcohol or drugs—that anything • A system that allows occupants sufficient time to en- less than automatic suppression may not be enough to save sure their survival them. • An inexpensive system Operation Life Safety 1995 Annual Residential Sprin- kler Activation Report provides data on 551 residential The NFPA Committee on Automatic Sprinklers devel- sprinkler activations with NFPA 13D or 13R systems from oped the initial 13D standard for the installation of sprinkler 1983 to July 31, 1995.3 This activation data indicates that systems in one- and two-family dwellings in 1975. NFPA approximately 50 percent of the total sprinkler activations 13D recommended that a sprinkler system provide a dis- 2007 Automatic Sprinkler Systems for Residential Occupancies Handbook Supplement 4 • Residential Sprinkler Systems 225 TABLE S4.2 Manufactured Home Fires in the United States, 1980 to 2002, Reported to Fire Departments Direct Property Damage (in millions) Civilian Civilian Current In 2002 Year Fires Deaths Injuries Dollars Dollars 1980 29,700 410 860 $135 $295 1981 27,100 530 850 $142 $280 1982 28,300 460 1,020 $145 $270 1983 26,300 480 870 $167 $301 1984 26,000 380 820 $193* $334* 1985 25,800 550 860 $174 $291 1986 25,400 410 840 $169 $278 1987 22,900 450 800 $140 $221 1988 23,600 510 960 $157 $238 1989 20,200 430 920 $140 $203 1990 19,100 380 750 $170 $235 1991 19,800 370 920 $190 $251 1992 19,300 380 850 $157 $201 1993 20,100 400 920 $201 $250 1994 19,200 350 870 $148 $179 1995 18,200 430 860 $154 $182 1996 17,900 440 800 $173 $199 1997 17,500 320 650 $158 $177 1998 15,500 190 640 $144 $159 1999 13,600 (13,300) 200 (200) 560 (560) $125 ($124) $135 2000 12,900 (12,100) 270 (270) 510 (510) $128 ($128) $134 2001 14,600 (12,200) 270 (270) 630 (600) $119 ($118) $120 2002 17,200 (13,300) 210 (210) 550 (510) $135 ($134) $135 Note: All fires are fires reported to U.S. municipal fire departments and so exclude fires reported only to federal or state agencies or industrial fire brigades. National estimates are projections. Casualty and loss projections can be heavily influenced by the inclusion or exclusion of one unusually serious fire. Fires are estimated to the nearest hundred, deaths and injuries to the nearest ten, and direct property damage to the nearest million dollars. Inflation adjustment to 2002 dollars is done using the consumer price index. Statistics shown in parentheses are without allocation of confined fires. ‘‘Confined fires’’ refer to fires confined to chimneys, cooking equipment (e.g., ovens, pots, pans on stoves), furnaces, or trash containers. Such fires do not have to be coded for most details, including manufactured home versus other dwelling. Confined fires in manufactured homes are estimated based on the manufactured home share of all other fires in one- and two-family dwellings. *This reflects the effect of one National Fire Incident Reporting System (NFIRS) fire reported to have a loss of $10 million, which therefore added $24.2 million to the national estimates total in current dollars. Source: John R. Hall, Jr., Manufactured Home Fires, Fire Analysis & Research Division, National Fire Protection Association, Quincy, MA, 2005. charge density rate from the sprinklers of 0.1 gpm/sq ft of sprinkler flow of 25 gpm for 10 minutes, resulting in the floor area for the single sprinkler with the largest area of 250-gal stored water supply.