Gap and Statistical Analysis on Housing Sprinkler Systems

Transcription

1 on Housing Sprinkler Systems December 2010

2 on Housing Sprinkler Systems Prepared for: National Research Council of Canada (NRC) Institute for Research in Construction Canadian Codes Centre Prepared by: 1580 Kingston Road Toronto Ontario M1N 1S2 Phone: (416) Fax: (416) altusgroup.com December 9, 2010

3 EXECUTIVE SUMMARY was retained to provide a gap and statistical analysis on single family housing automatic fire sprinkler systems on behalf of National Research Council of Canada (NRC). Automatic fire sprinkler systems built into buildings are said to provide a superior response to fire situations. Automatic fire sprinkler systems are mandatory across a wide array of building types within the National Building Code of Canada but these do not include single family homes. Single family homes (single detached, semi detached dwellings and row housing) can be subject to mandatory automatic fire sprinkler system requirements in some municipalities, but these local policies remain rare. In both Canada and the U.S. there are increasing pressures to introduce requirements for automatic fire sprinkler systems in new single family construction. In recent years a large body of technical, statistical and economic evidence has emerged that aims to illustrate the degree of effectiveness of these policies. The conclusiveness of these studies varies considerably. The number of concurrent measures and policies introduced in recent decades confounds the study of the effectiveness of a measure such as mandatory automatic fire sprinkler systems. These have also had the effect of reducing the number of fires, the extent of fire damage and the number of fire related deaths and injuries associated with single family house fires. Literature and Statistical Gaps Although there have been an extensive number of studies on the home automatic fire sprinkler system, research gaps in several areas still exist. Future studies could help fill these research gaps and assist regulators on whether to implement a mandatory requirement for automatic fire sprinkler installation in residential structures. These research areas include: Technical studies on the performance of automatic fire sprinkler systems in Canada, especially the performance in single family homes under extremely cold weather; Studies on the effectiveness of automatic fire sprinkler systems using identical residential structures, such as controlled experimental studies, on Housing Sprinkler Systems Page i

4 comparing the impact of automatic fire sprinklers on identical residential structures at a research facility; Cost benefit studies that are more conclusive on various costs of the automatic fire sprinkler system, including water damage cost from automatic fire sprinkler failure incidents. To actually estimate the benefits of the automatic fire sprinkler system, researchers should compare homes with similar structures and minimize the differences between homes with automatic fire sprinklers and the ones without; and Feasibility studies on establishing a national fire incident reporting system in Canada that is similar to the NFIRS in the United States. The Canadian Fire Experience The Canadian fire experience has been characterized by a steady decline in the average number of fires over the period. Despite the population increase (and household increase) over this period, the number of fires per capita has also been falling. The experience in fires in one and two family dwellings has shown a similar pattern of declining numbers and a falling per capita rate over the study period. The number of injuries and the per capita rate of injuries in fires in residential structures have fallen over the study period, except for an increase in both over the period; and The absolute number of deaths and the per capita death rate in fires has also declined over the study period. Fire Losses and Casualties Aggregate Findings In the study areas considered, the data show that the presence of automatic fire sprinkler systems greatly reduce injuries. However, fire losses appear to be relatively unchanged with the presence of smoke/heat alarms, and noticeably higher with the presence of automatic fire sprinkler systems. Finally, only two deaths have been reported in homes with automatic fire sprinklers (although the resultant death rate calculates higher). on Housing Sprinkler Systems Page ii

5 Cost Benefit of Automatic Fire Sprinkler System Ordinance The findings from the statistical analysis show that with the mandatory implementation of automatic sprinkler systems in all new single family homes in Canada, there is likely to be a reduction in the amount of property damage and the number of injuries related to fire situations. The evidence is less conclusive on the matter of whether sprinkler systems would lead to a reduction in the number of deaths. There are considerable costs involved in installing, maintaining and related to failure of automatic sprinkler systems, and a mandate to install automatic sprinkler systems in all homes would impose these costs onto the buyers of new homes. Comparing these costs to the illustrated benefits in terms of injuries, shows that over the first 20 years of a nation wide automatic sprinkler system mandate for single family homes, the cost per injury avoided is some $2.9 million. Due to the ambiguity of the statistical analysis with respect to deaths, it is hard to assign a cost per death avoided (the statistical analysis actually pointed to a potential increase in deaths related to sprinklers in single family homes). However, even if we assume absolute effectiveness of sprinklers that is they would be effective in stopping all deaths in fire situations in single family homes built after 2010 the cost per death avoided would be in the order of $29 million. If a more likely scenario is considered (sprinklers leading to a 10% reduction in deaths), then the costs would rise to the order of $290 million per death avoided. These costs appear to be well in excess of the typical value of statistical life considered typical for regulatory measures. on Housing Sprinkler Systems Page iii

6 TABLE OF CONTENTS Page EXECUTIVE SUMMARY... i 1 INTRODUCTION Background Structure of the Report Caveat BACKGROUND The Model National Building Code Fire Deaths in Canada Causes and Statistical History Fire Detection Devices Automatic Fire Sprinkler Systems Estimated Fire Losses Automatic Fire Sprinkler System Costs LITERATURE REVIEW AND GAP ANALYSIS Studies Focused on Technologies Studies Focused on Effectiveness Studies Focused on Cost Benefit State of Fire Related Statistics in Canada and the United States Literature and Statistical Gaps CANADIAN FIRE EXPERIENCE Historic Fire Incidents Historic Fire Injuries Historic Fire Deaths Detectors Conclusions STATISTICAL ANALYSIS ON THE EFFECTIVENESS OF AUTOMATIC FIRE SPRINKLER SYSTEMS Methodology Fire Database Pairwise Statistical Analysis Aggregate Findings...43 on Housing Sprinkler Systems Page iv

7 6 COST BENEFIT OF AUTOMATIC FIRE SPRINKLER SYSTEM ORDINANCE Scenario for Single Family Housing Starts in Canada by Five Year Period to Scenario for Single Family House Fires in Canada by Five Year Period to Cost of Installation in 100% of Single Family Housing Starts in Canada, by Five Year Period, from Value of Gap in Injuries in Terms of Costs of Automatic fire sprinklers Value of Gap in Deaths in Terms of Costs of Automatic fire sprinklers Conclusion...54 APPENDIX A FIRE DATA SOURCES APPENDIX B CANADIAN TREND DATA APPENDIX C PAIRWISE STATISTICAL ANALYSIS OF SUBJECT AND COMPARATOR JURISDICTIONS APPENDIX D BUILDING FIRE STATISTICS FOR SUBJECT & COMPARATOR JURISDICTIONS APPENDIX E COST BENEFIT ANALYSIS APPENDIX F BIBLIOGRAPHY on Housing Sprinkler Systems Page v

8 1 INTRODUCTION was retained to provide a gap and statistical analysis on single family housing automatic fire sprinkler systems on behalf of National Research Council of Canada (NRC). 1.1 BACKGROUND Automatic fire sprinkler systems built into buildings are said to provide a superior response to fire situations. Automatic fire sprinkler systems are mandatory across a wide array of building types within the National Building Code of Canada but these do not include single family homes. Single family homes (single detached, semi detached dwellings and row housing) can be subject to mandatory automatic fire sprinkler system requirements in some municipalities, but these local policies remain rare. In both Canada and the U.S. there are increasing efforts to introduce requirements for automatic fire sprinkler systems in new single family construction. In recent years a large body of technical, statistical and economic evidence has emerged that aims to illustrate the degree of effectiveness of these policies. The conclusiveness of these studies varies considerably. Studying the effectiveness of a measure such as mandatory automatic fire sprinkler systems is confounded by the number of concurrent measures and policies introduced and proliferating in recent decades. These other concurrent measures have also had the effect of reducing the number of fires, the extent of fire damage and the number of fire related deaths and injuries associated with single family house fires. 1.2 STRUCTURE OF THE REPORT This report contains a number of chapters: Chapter 2 covers the literature review undertaken and the gap analysis. Chapter 3 presents fire statistics for Canada. Chapter 4 examines the effectiveness of automatic fire sprinkler systems in reducing casualties (injuries and deaths) and the cost of damages in fires. on Housing Sprinkler Systems Page 1

9 Chapter 5 Canadian forecasts Chapter 6 forecast of fire statistics for the study areas In addition, there are 6 Appendices: Appendix A contains a description of the various fire data sources; Appendix B includes Canadian annual trend data; Appendix C show the background calculations and findings from the pairwise statistical analysis of subject and comparator jurisdictions; Appendix D contains detailed building fire statistics for the subject and comparator jurisdictions, in annual format; Appendix E shows the detailed calculations and findings from the cost benefit analysis; and Appendix F includes the bibliography for the literature review. 1.3 CAVEAT This analysis has been prepared on the basis of the information and assumptions set forth in the text. However, it is not possible to fully document all factors or account for all the changes that may occur in the future. This report relies on information from a variety of secondary sources. While every effort is made to ensure the accuracy of the data, we cannot guarantee the complete accuracy of the information used in this report from these secondary sources. This report has been prepared solely for the purposes outlined herein and is not to be relied upon or used for any other purposes or by any other party without the prior written authorization of. on Housing Sprinkler Systems Page 2

10 2 BACKGROUND Public safety has always been the top priority of the government. To minimize death from fire incidents, the government introduced various fire prevention and protection measures in the model building and fire codes. This section provides background information related to the national building code system in Canada, fire incidents and fire mortality in Canada, especially as it relates to the use of smoke alarms and automatic fire sprinkler systems. 2.1 THE MODEL NATIONAL BUILDING CODE The National Building Code of Canada 2005, together with the National Plumbing Code of Canada 2005 and the National Fire Code of Canada 2005, is an objective based National Model Code that can be adopted by provincial and territorial governments. In Canada, provincial and territorial governments have the authority to enact legislation that regulates building design and construction within their jurisdictions. This legislation may include the adoption of the National Building Code (NBC) without change or with modifications to suit local needs, and the enactment of other laws and regulations regarding building design and construction, including the requirements for professional involvement (Preface, 2005 NBC). In addition, regulating buildings was historically the responsibility of municipalities. Today, Montreal and Vancouver retain this right in their charter. The National Building Code (NBC) sets out technical provisions for the design and construction of new buildings. It also applies to the alteration, change of use and demolition of existing buildings. The NBC establishes provisions to address the following four objectives, which are fully described in Division A of the Code: Safety; Health; Accessibility for persons with disabilities; and Fire and structural protection of buildings (National Building Code, Preface, 2005) on Housing Sprinkler Systems Page 3

11 2.2 FIRE DEATHS IN CANADA CAUSES AND STATISTICAL HISTORY According to Statistics Canada s Vital Statistics Death Database, on average, structure fire incidents were responsible for some 176 deaths per year in Canada between 2000 and 2006 (Figure 1). This represents about 1.3% of the total accidental deaths in Canada and this ratio has been relatively stable over the period of Figure 1 Death from Structure Fire Incidents, Canada, Persons Number of Fire-Related Deaths % of Total Accidental Deaths Percent Source: based on data from Statistics Canada Most victims of fire incidents die from smoke or toxic gases (i.e. smoke inhalation) created by the fire rather than from burns. Children and seniors are at the greatest risk of death during a fire incident. Smoking is the leading cause of fire related deaths and cooking is the primary cause of residential fires (CDC, Website). In 2002, residential fires represented some 41% of all the fires in Canada and accounted for about 82% of fire fatalities 1 (Tracey, 2007). To reduce the death toll from residential fire incidents, the federal and provincial governments introduced various measures in building codes. 1 The author of the report does not specifically define what types of construction are encompassed in the use of the terms residential or all. on Housing Sprinkler Systems Page 4

12 2.3 FIRE DETECTION DEVICES The smoke alarm is one of the most effective and low cost technologies that can save lives. Alarms alert people in the home to the presence of smoke and fire. This provides additional time for people to escape. The federal and provincial governments first started to require smoke alarms in new buildings around 1980 and in existing buildings during the mid 1980s (CMHC, 2005). Over the years, provincial regulators expanded the scope for smoke alarm ordinances. For example: New Brunswick first required smoke alarms to be installed in every bedroom on or near the ceiling of multi unit residential buildings and institutional buildings in 1982; In 1991, Newfoundland and Labrador introduced the Fire Prevention and Smoke and Fire Alarm Regulations that required smoke alarms to be installed in all new dwelling units; As of January 2006, Regina required all rental units to have hard wired smoke alarms installed, and the smoke alarms should be tested every 6 months; Effective March 1, 2006, it is the law for all Ontario homes to have a working smoke alarm on every storey and outside all sleeping areas; Although smoke alarm requirements were introduced into the British Columbia Building Code in 1979, it did not require smoke alarms in all existing dwelling units such as private homes until May 1, Owners of private dwelling units built before March 31, 1979 are now also required to have smoke alarms installed; In Alberta, under the provincial Fire code, all dwelling units must have a smoke alarm installed, whether new construction or old; homes constructed after 1997 are required to have at least one alarm on each storey, whereas homes constructed prior to 1997 only require one alarm (additional alarms may be required for larger or multi level dwellings); and Nova Scotia does not have provincial legislation concerning smoke alarms. However, the Regional Municipality of Halifax has a by law that states that every residential occupancy shall be equipped with a smoke alarm. on Housing Sprinkler Systems Page 5

13 2.4 AUTOMATIC FIRE SPRINKLER SYSTEMS An automatic fire sprinkler system is a fire protection measure consisting of a water supply system, a water distribution piping system, and fire sprinkler heads, which are automatically activated by extreme heat. The National Building Code was amended in 1995 to require automatic fire sprinklers in large residential buildings. Since then, many provinces followed the lead and amended their building code accordingly (MMAF, 2008). Ontario required automatic fire sprinklers in large residential buildings effective on April 1, All Canadian provinces require the installation of automatic fire sprinklers in newly built nursing homes. Nova Scotia was the first to adopt this measure in The rest of the country adopted the requirement in the 1990s (CBC Marketplace). Some Canadian municipalities, mainly located in British Columbia, have adopted the automatic fire sprinkler ordinance for single family housing, including: Vancouver: ordinance adopted in 1990; Port Coquitlam: ordinance adopted in 1999; District of Maple Ridge: ordinance adopted in 2003; and Chilliwack: ordinance adopted in ESTIMATED FIRE LOSSES Structure fires not only cost lives, but also cause monetary loss. Sometimes it is hard to estimate the true damage caused by a structure fire. Under the National Fire Incident Reporting System 5.0 in the U.S., the value loss is defined as: Rough estimation of the total loss to the structure and contents, in terms of the cost of replacement in like kind and quantity. This estimation of the fire loss includes contents damaged by fire, smoke, water, and overhaul. This does not include indirect loss, such as business interruption (FEMA, 2008). As the definition indicates, the dollar loss is just the rough estimation provided, typically at the site of the incident, from fire department officials. The true cost of a residential fire could be much higher than the fire department estimates. More accurate damage estimates could be compiled on Housing Sprinkler Systems Page 6

14 from insurance claim data. However, these data tend not to be available for analytical use due to privacy issues. 2.6 AUTOMATIC FIRE SPRINKLER SYSTEM COSTS The main concern about automatic fire sprinkler mandates in housing is the system installation costs to new home buyers, and the resulting effects on housing affordability. Various studies from both the U.S. and Canada have investigated this issue over the years and provide some guidance (Figure 2). There are a wide range of estimates for the installation cost as per square foot: The cost estimate from the U.S. ranges from $0.65 USD per sq. ft up to $1.60 USD per sq. ft. depending on the housing type, automatic fire sprinkler system design, materials used, and local building codes; In Canada, the average cost ranges from $1.43 CAD to $2.37 CAD depending on pipe materials (plastics vs. copper) and location (urban vs. rural). The overall average is approximately $1.70 CAD; Annual maintenance costs are also a consideration. CMHC estimates homeowners face $20 CAD to $35 CAD per year in maintenance costs; and Evidence from the literature shows that aside from the differences in local building codes and fees, the regional differences in automatic fire sprinkler installation costs are limited. The main determinant factors of automatic fire sprinkler costs are the system design and type of materials used. Over time, one should expect the installation cost to gradually decline, partially due to innovation and improved installation efficiencies/economies. The experience in Scottsdale, Arizona suggests that installation costs of automatic fire sprinkler systems for production homes declined from $1.14 USD per sq. ft. in 1986 to $0.59 USD in 1996 (Rural/Metro Fire Department, 1997). The consistent reduction in the installation price of residential automatic fire sprinkler systems in Scottsdale is related to (Rural/Metro Fire Department, 1997): The increased size of the market resulting from the mandatory requirement; Established standards are identified for all builders; on Housing Sprinkler Systems Page 7

15 Increased competition for the available business; Better availability and quality of different materials (i.e. CPVC versus steel); and An increase in the efficiency of plumbing contractors who install the systems, resulting in better and quicker installations. By contrast, the CMHC studies show there to be little change in automatic fire sprinkler system cost in Canada between 1998 and 2005 (CMHC, April 2005). This might be because there are only a limited number of singlefamily homes installing automatic fire sprinklers in Canada, resulting in the lack of an economy of scale. on Housing Sprinkler Systems Page 8

16 Figure 2 Sprinkler Cost Estimate from Literature Title Home Fire Sprinkler Cost Assessment Author Year Single Detached Semi-Detached Townhouse New port Partners for the Fire Protection Research Foundation 2008 The average cost of installing sprinkler is $1.60 USD per sprinklered sq. ft. and $1.49 USD w hen accounting for any available credits. Maintenance Cost Variation by Region Variables Influence the Cost Sprinkler System Requirements and Extent of Coverage Type of Pipe Used Water Source Permit and Inspection Fees System Design Type (Multi-purpose systems are generally cheaper than standalone ones) Type of Foundation Economic Analysis of Residential Fire Sprinkler Systems 1 Hayden Brow n, funded by United States Fire Administration 2005 $0.62 USD per sq. ft. for a tw o-storey colonial house $0.84 USD per sq. ft. for a threestorey tow nhouse $0.71 USD per sq. ft. for a singlestorey ranch Annual inspection cost: $100 USD or $200 USD Labour is part of the estimated costs, how ever, it is kept at a Sprinkler System Design constant rate. It assumes that Housing Type the installation requires a 2- Mark-ups on materials person crew, 13 hours of w ork A 15 Year Update on the Impact and Effectiveness of the Scottsdale Sprinkler Ordinance 2 Jim Ford, Assistant Chief / Fire Marshal Scottsdale The installation cost averages $0.65 USD per sq. ft. for typical homes. Cost Study of Sprinkler Installations J.C.Weibe for Alberta Municipal Affairs 1989 For a 1,940 sq. ft. side-split home in an urban location, cost is $1.43 CAD per sq. ft (plastic) and $2.37 CAD (copper). The cost in rural locations w ould be $2.47 CAD per sq. ft (plastic) and $3.67 CAD (copper). Costs and Benefits of Installing Fire Sprinklers in Houses 3 CMHC 1990 Typical installation costs of sprinklers averaged $4,750 CAD per housing unit. $35 CAD per year The costs in rural areas are generally higher than in urban Type of Pipe Used areas due to the w ater source. Location - Urban vs. Rural Costs and Benefits to Municipalities of Mandatory Residential Fire Sprinklers CMHC 1998 Typical installation costs of sprinklers averaged $1.70 CAD per sq. ft. $200 CAD per home every 10 years Fire Experience, Smoke Alarms and Sprinklers in Canada Houses: CMHC Research to CMHC 2005 Typical installation costs of sprinklers averaged $1.75 CAD per sq. ft. Cost Benefit Analysis for Residential Sprinklers in Canada Sean A. Tracey prepared for NRC 2009 The average for the installation of a sprinkler system is estimated to be $3,500 CAD per system. The costs in rural areas w ill be greater than the average due to w ater supply issues, but these w ill be balanced against cost savings in urban areas. Note: 1 The costs for colonial, tow nhouse and ranch are based on the 50% mark-up on material scenario. Those numbers are also quoted in the Benefit-Cost Analysis of Residential Fire Sprinkler System study. 2 The installation cost to average $0.55 USD and $0.75 USD per square foot for typical homes. 3 Based on the midpoint of the estimated cost range betw een $2,800 CAD and $6,700 CAD for a typical home. 4 Based on the midpoint of the estimated cost range betw een $3,000 CAD and $4,000 CAD for a 2,000 sq. ft. sprinklered area. Source: on Housing Sprinkler Systems Page 8

17 2.6.1 Estimated 2011 Automatic Fire Sprinkler Costs in Canada Based on the range of cost data in the studies, and considering the data in the framework of 2011 based Canadian dollars (i.e. values from the literature both converted for exchange rate where applicable and inflated to 2011$ values 2, Figure 3 presents a summary of the range of per square foot costs as assessed in the literature. Based on this summary, a typical value of about $2 per sq. ft. appears to be a reasonable summary of the literature. Figure 3 Automatic Fire Sprinkler Cost Estimates from the Literature 2011 $CAD per sq. ft A B C D E F G Source: A - Cost Study of Sprinkler Installations; B - Costs and Benefits to Municipalities of Mandatory Residential Fire Sprinklers; C - Fire Experience, Smoke Alarms and Sprinklers in Canada Houses: CMHC Research to 2005; D - Cost Benefit Analysis for Residential Sprinklers in Canada; E - Home Fire Sprinkler Cost Assessment; F - A 15 Year Update on the Impact and Effectiveness of the Scottsdale Sprinkler Ordinance; G - Economic Analysis of Residential Fire Sprinkler Systems 2 Values from the literature were inflated to 2011$ by assuming that the annual increase in installation cost is approximately 2%. on Housing Sprinkler Systems Page 9

18 3 LITERATURE REVIEW AND GAP ANALYSIS This section entails a comprehensive review examining the existing body of literature, studies and statistics that relate to home automatic fire sprinkler systems, fire incidents, as well as fire related injury, loss of life and property losses both from within Canada and the United States. In addition, the literature review assesses obvious gaps in the body of literature that could be followed up in additional research by the National Research Council (NRC). There is a wide array of studies and reports related to fire statistics, fire prevention and extinguishing technologies, especially looking at residential automatic fire sprinkler systems. These studies could be broadly divided into four main categories: technologies, effectiveness, cost benefit and statistics. 3.1 STUDIES FOCUSED ON TECHNOLOGIES Studies on the technical aspect of residential fire incidents and the performance of automatic fire sprinkler systems are relatively comprehensive. Those studies are fairly straightforward. Research ranges from experimental fire design to building code standards that relate to the installation of the automatic fire sprinkler system. Some of the main findings from these studies include: The basement fire scenario, with an open basement doorway, was more severe than the fire scenario with a closed doorway to the structural integrity of unprotected floor assemblies and the life safety of occupants (NRC, 2008); The 1993 report of the Part 3 Joint Task Group on Automatic Sprinklers to the Standing Committee on Fire Protection and Occupancy recommends that changes should be made to the National Building Code to extend the use of automatic fire sprinkler systems in buildings regulated by the Code (NRC, 1993); NRC finds that the pipes and fittings of the automatic fire sprinkler system can withhold exposure to temperatures above the rated temperature of 93 C at 552 kpa for 140 s and can successfully control the fire, based on experiments at Kemano Village. Technical data obtained from this study can provide guidance for future studies with an increased fire challenge to automatic fire sprinkler systems (NRC, 2002); on Housing Sprinkler Systems Page 10

19 A detailed U.S. study conducted by the National Institute of Standards and Technology on the performance of home smoke alarms concludes that smoke alarms (either the ionization type or the photoelectric type) consistently provide time for occupants to escape from most residential fires. The study credits the home smoke alarm as the greatest success story in fire safety in the last part of the 20 th century, because it alone represented a highly effective fire safety technology with leverage on most fire death problems that were widely adopted in a relatively short period (NIST, 2008); In a 1983 research note, the NRC analyzed the causes of automatic fire sprinkler system failure during a fire incident and concluded that most solutions to reduce failures and improve the reliability of automatic fire sprinkler systems could be easily accomplished in new buildings (NRC, 1983); and There is also research on automatic fire sprinkler sensitivity and response time, automatic fire sprinkler water distribution, multi purpose piping systems, residential water mist systems, etc. Although there have been comprehensive technical studies on the use of the residential automatic fire sprinkler system in the U.S., there is a lack of research on the performance of automatic fire sprinkler systems in Canada, especially the performance of single family automatic fire sprinkler systems under extremely cold conditions. A recent U.S. study quotes exposure to freezing conditions as one of the common factors causing automatic fire sprinkler systems to fail (NFPA, Jan. 2009). 3.2 STUDIES FOCUSED ON EFFECTIVENESS Studies on the effectiveness of the residential 3 automatic fire sprinkler system generally conclude that it is an effective fire extinguishing technology in reducing fire damages and saving lives during an incident. A comprehensive study of the use of the automatic fire sprinkler system in all types of structures in the U.S. concludes (NFPA, January 2009): Automatic fire sprinklers deploy in 95% of all reported structure fires large enough to activate automatic fire sprinklers and, when they 3 Generally single family. on Housing Sprinkler Systems Page 11

20 operate, are effective at suppressing the fire source 96% of the time, resulting in a combined performance rate of 91%; This combined performance rate is higher than for dry chemical systems (58%), carbon dioxide systems (84%) and foam systems (82%); In addition, the rate of property damage is reduced by 45% to 70% for most property uses; and When automatic fire sprinklers present in all types of structures (that are not under construction) fail to operate, the main reason is due to the shutoff of the system before the fire began (63% of failures), followed by lack of maintenance (14%) and inappropriateness of the system for the type of fire (11%) (Figure 4). Figure 4 Reasons Why Automatic Fire Sprinklers Failed to Operate, System shut off before fire 63 Lack of maintenance 14 Inappropriate system for fire 11 Manual intervention defeated system 9 Damaged component Percent Source: based on data from U.S. Experience with Sprinklers and Other Automatic Fire Extinguishing Equipment, National Fire Protection Association, January 2009 A study, conducted by Building Research Establishment Ltd. in the U.K. on the effectiveness of the residential automatic fire sprinkler system, concludes the effectiveness of automatic fire sprinklers is more or less independent of property type, and lies in the following ranges 4 (Williams, 2004): Reduction in the number of deaths: 55% to 85%; 4 The study included single and multiple occupancy houses, flats and care homes as classification of residential fire types, and for the purposes of its cost benefit analysis sprinkler effectiveness was assumed to be independent of property type. on Housing Sprinkler Systems Page 12