|The Case for Residential Fire Sprinklers|
fire sprinklers represent a different approach and technology. They add fire
suppression to the early warning of smoke detectors. First, a heat sensitive
element-called the fusible link-detects the heat from fires. Second, the
sprinkler releases water on the fire, extinguishing the fires or confining
the fire until the fire department arrives. It is the ability of sprinkler
systems to control or extinguish fires in their early stages that makes
them such a critical tool in fire protection strategy.
Each sprinkler head responds independently, so that when heat is detected and the sprinkler goes off-which is referred to as "activation"-it puts water only on the affected area and not throughout the rest of the house or building. In roughly 90 percent of all documented sprinkler activations in residences, one sprinkler has been sufficient to control the fire15.
The Appeal of Sprinkler Systems
The cost of fire sprinklers is significant compared to smoke detector costs. But the appeal of sprinklers is also significantly geared, for several basic reasons:
Sprinklers achieve these benefits with proven automatic technology. Like other state-of-the-art automatic restraint systems (e.g. airbags), they do not rely on changed human behavior to prevent accidents and loss. The vast majority of all residential fires today are estimated to have behavioral causes-like careless smoking, unattended cooking or children playing with fire. While we cannot design adults to never smoke carelessly or all children to not hide in the closet after they have accidentally set a fire, we can design sprinkler systems to control the results of this behavior.
Sprinklers offer opportunities for more effective use of fire and emergency service resources. Fire sprinklers systems do not necessarily reduce the number of calls for firefighters, but they do reduce the severity of the fire, thereby reducing danger to firefighters and complexity of response. And because sprinklers could diminish the requirements of fire suppression, they also make it possible for the fire service to allocate more resources to important Emergency Medical Service (EMS) demands, search and rescue needs, etc.16.
Ten years ago there was little experience with how sprinklers-if they were installed in significant numbers of residential dwellings-would affect the nationwide fire problem. Fortunately, we are now beginning to build a significant body of experience in various locations across the country.
Much of this work has been supported by the United States Fire Administration (USFA) as part of a concerted public and private sector effort to determine the appropriate role of residential sprinklers in the country's overall fire suppression and protection strategy. Some of the most extensive experience with residential sprinklers is reflected in the following locations or projects:
Operation San Francisco, which in the early 1980s served as a national pilot project for residential sprinkler application and testing.
Operation Life Safety, a public/private consortium that, among other activities, monitors residential sprinkler activations all across the country, and tracks the human and property loss statistics for each of those activations.
Cobb County, Georgia, which has tested voluntary incentives, resulting in reduced construction costs, for builders who install sprinklers in new multi-family housing.
Napa, California, where a series of ordinances now require automatic sprinkler protection for a variety of new single and multi-family residences, including all new homes built more than 1.5 miles from a fire station.
Prince George's County, Maryland, which has required automatic fire sprinklers for all new residential construction, including single family dwellings, since 1987.
Scottsdale, Arizona, which passed the nation's most comprehensive sprinkler ordinance in 1985, requiring an automatic sprinkler system in every room of every new industrial, commercial or residential building in the city.
Several "retrofit" demonstration projects, supported by USFA and the National Association of Home Builders Research Center (NAHB-RC), to design and install sprinklers in low income single and multi-family housing units undergoing rehabilitation in a number of U.S. cities.
A self-contained, limited water supply sprinkler research and development project of USFA targeting mobile home fire safety.
Several demonstration projects, supported by USFA and NAHB-RC to identify barriers to residential sprinklers and solutions to these problems.
Port Angeles, Washington has been requiring sprinklers since 1986 in all newly constructed multi-family residential properties. They have also implemented a combination residential sprinkler system program reducing the cost of sprinkler installation by 30%. Subdivisions four minutes from a fire station are required to be sprinklered.
It is possible to draw a number of important conclusions about residential sprinklers from the projects and experience just listed. Most Significantly:
1. Residential Sprinklers Save Lives
The evidence on this point is overwhelming. There has not been a single residential fire fatality in a residence with a sprinkler system in either Napa, California or Cobb County, Georgia since the inception of those programs. There has not been a single fire fatality in Prince George's County, Maryland in a building with a sprinkler system. Scottsdale, Arizona credits sprinkler systems with saving up to 52 lives since the ordinance passed in 1985.
A 1984 report by the Bureau of Standards/National Institute of Standards and Technology estimated that the effect of adding fire sprinklers when smoke detectors are already present could reduce the number of fire fatalities by 63 percent.
A NFPA analysis of national data, collected from 1983 to 1992, indicates the number of fire deaths per 1,000 fires was reduced by 57 percent in homes with sprinklers.
2. Residential Sprinklers Reduce Property Loss
Again, the evidence is dramatic. Cobb County, Georgia and Napa, California reported minimal or incidental damage for all of their sprinkler activations, against potential losses extending into the millions, especially for Cobb's multi-family units. Nationally, average property loss in homes with sprinkers is 38% lower than homes without sprinklers, according to a NFPA survey of home fires reported to fire departments from 1983 - 1992.
Where communities have a great deal of experience with residential fire sprinklers the property loss reduction can be much higher. In Scottsdale, fire loss hit a ten-year low in 1992, despite nearly 30 percent population growth in the city in the previous decade. Scottsdale's tracking data show that the average loss in a home with sprinklers in the city, since 1985, has been $1,382, while the figure for the average loss in a house without sprinklers is $3,928.
3. Residential Sprinklers Costs Can Be Substantially Reduced and Offset
Builders are understandably reluctant to add to the cost of new construction, especially in a tough economy and at a time when there is already concern that large numbers of Americans are priced out of the new housing market.
Important research is underway to advance the technology, reduce the cost and identify ways to overcome barriers to widespread use. There is increasing evidence that innovations like combining the sprinkler system with the in-home plumbing system, streamlining of the design and permit process, acceptance of building code alternatives and new ideas in site plans for subdivisions can change the economics of sprinkler decisions.
Building code alternatives that communities can consider include: reduction in fire rated gypsum wall board requirements, alterations to attic fire stops, and reduced fire retardant standards for both masonry walls and doors. Cobb County, GA, is a national leader in building code alternatives, particularly for multi-family units.
More widespread is the use of alternatives in site plans for subdivisions that use residential fire sprinklers. Variations in length of set back, density of housing units, street width, turn around radius in cul-de-sacs, water main size and distance between fire hydrants, among others, produce cost savings for builders.
The United States Fire Administration is sponsoring a program with the National Association of Home Builders Research Center and the International City Management Association to identify barriers to residential fire sprinklers and test alternatives. They have developed and are testing a guide to simplify residential fire sprinkler system design and engineering and are working with combined domestic water and sprinkler system installations. In Cedar Rapids, IA, demonstrations, using the guide and a combined system, whole-sale costs have dropped under 50 cents per square foot. In their Prince George's County, MD, work, and in eight other sites, the guide has dropped costs to about 80 cents per square foot. Combined systems are expected to reduce these costs further.
Similar trends are reported for Scottsdale, Arizona, which grew by nearly 30, percent in the seven years after passage of the sprinkler ordinance. Today, Scottsdale citizens pay 30-50 percent less for fire services than residents in surrounding communities. But at the same time, according to Scottsdale officials, the city's Rural/Metro fire service is able to employ more than 50 percent more fire prevention personnel than the regional average.17 These individuals spend their time in public fire education, building inspection, plan review, arson investigation, and fire prevention administration. This reallocation of available resources, to growing EMS demands or to other basic public services (education or police for example) can be a significant benefit to localities across the country.
5. Residential Sprinklers Have Potential to Reduce Homeowner and Property Insurance Costs
At the present time, insurance reductions are much more common for multi-family units with sprinklers, or for institutional kinds of residential properties-nursing homes, dormitories, etc.-than they are for single family units. Owners of four of the five multi-family units involved in the USFA sprinkler retrofit project received reduction in insurance premiums, for example, after installation of sprinklers. The rate of reduction ranged from 4-40 percent.18 In the one and two family unit market, reductions occur, but thus far the timetable for action is longer and the percentages of reduction less dramatic. Collectively, more work is necessary to encourage the insurance industry to carry long-standing commercial insurance discounts for sprinkler systems to the residential market.
In general, the Insurance Service Office (ISO) recommends a 13 percent discount for a one or two family residential sprinkler system meeting NFPA 13D standards-with 2 percent more if smoke detectors are also present. This is from the total premium, not just the fire portion.19
The evidence from communities that have led the way with voluntary sprinkler programs or ordinances suggests that benefits to date are substantial, for both saved lives and saved property. The evidence further suggests that down-the-road benefits, in terms of reduced construction and insurance costs, and greater control of future fire service cost increases, will also be substantial.
Protecting Lives and Property with Residential Sprinklers: Where are We Today?
1. The incidence of residential sprinklers nation-wide is extremely low.
Today, residential sprinklers are probably found in fewer than one percent of all one and two family housing units. The nationwide figure for multi-family units, while believed to be greater, is probably less than 10 percent. Incidence of residential sprinklers in communities with ordinances and voluntary programs ran considerably higher-Prince George's County in Maryland estimates that 20 percent of all multi-family units, and 4 percent of one and two family units, now have sprinkler systems, for example. But nationwide, the penetration numbers are very low, especially if existing housing stock, as opposed to new, is considered.
2. A substantial amount of the research and demonstration work, to develop the technology for quick, reliable, and affordable sprinklers, has been completed.
USFA-supported research in the last 15 years has produced significant technological gain. The basic technology has been made to activate much faster (sprinklers now exist for residential use that have a response time five times faster than commercial sprinklers). Sprinklers have been adapted to meet the particular requirements of virtually every kind of residential housing.
Sprinklers are no longer unattractive (in the sense of being less obtrusive to the homeowner). Sprinklers are increasingly less demanding in terms of water flow-in many instances they operate off the domestic water supply and do not require any special lines or pumps. Low water volume units with self-contained water supplies have been developed to meet the particular requirements of manufactured homes, where fire danger is severe.
High priority research and development over the next few years needs to focus on sprinkler systems that will create the potential to give builders realistic cost saving construction alternatives when installing sprinklers in one and two family units. Especially important are "combined systems" in which the sprinkler system and domestic water supply are merged into a single component. It will also make retrofitting far more feasible economically.
We now have a Standard (NFPA-13) for large (In most commercial) buildings, Standards (NFPA-13D) for one- and two-family dwellings and manufactured homes, and NFPA-13R for residential occupancies up to and including four-stories in height.
An additional standard - NFPA 25 - (which replaces NFPA-13A/14A)-was added in 1992 and covers the inspection, testing and maintenance of water-based fire protection systems, including sprinkler systems in accordance with NFPA-13. This brings the critical issue of quality control under nationally recognized standards. Periodic inspection of sprinkler systems is important to insure that they perform as intended. Work continues to ensure that simplified methods of design and engineering can be brought to residential systems.
Additionally, water authorities in a number of communities around the country have adopted policies of charging fees to homeowners for the initial connection of the sprinkler system to the water supply (connection fee), and for maintaining the availability of water, should it be needed (standby charge).
The amount of the fees varies widely, and in some cases clearly constitutes a pronounced financial disincentive to sprinklers. In nearly 50 California communities surveyed in the first half of 1993, for example, the average residential connection fee is $1,646 and the average residential standby fee is $143 annually.20
Sprinkler proponents believe that these fees-especially the standby fees-are questionable policy. There is no charge to homeowners who have not protected their property with sprinklers for the far greater amount of water that is needed to suppress a fire once it occurs. They are working with national water supply organizations to develop a more rational approach.
At the state level, there is also action, especially from the National Association of State Fire Marshals which is playing a vigorous role, in cooperation with the United States Fire Administration, to ensure implementation of both of these acts. Some states have, in fact, enacted legislation on these issues.
8. Public awareness of the benefits of sprinklers is low.
Increased public awareness is the critical next step in the drive to sprinkler America's residential housing. There are three avenues for action:
Educate the public with the facts about residential fire sprinkler technology:
Residential fire technology has advanced reliability and responsiveness.
In experience to date, 90 percent of fires are contained with one documented sprinkler operating. Each residential fire sprinkler responds independently, resulting in fires rarely spreading beyond the room of origin.
A community with sprinklers will require significantly less water for fire suppression since a residential sprinkler uses as little as 10 to 18 gallons per minute, as compared to the 150 gallons per minute needed to manually suppress a small house fire.
Residential fire sprinklers have the potential to reduce fire death and property loss attributable to fire. They can do so without jeopardizing the affordability of the housing stock in this country. They can enhance the capacity of public officials to provide for the health and safety of all our citizens-including those most at risk, such as the elderly, the very young, and the disabled.
At the same time, residential sprinklers can help to flatten future expenditures for fire-without diminishing the quality of fire service and protection. This is vital in a time of distressed public sector budgets.
The United States Fire Administration gratefully acknowledges the support of a number of individuals and organizations in the preparation of this report. It is impossible to cite the guidance of every individual and organization and we apologize for any omittance. In particular we would like to acknowledge the support of the organizations involved in the Partners for Fire Safe Homes.
15. Operation Life Safety. "379 Activations."
16. Institute for Local Self Government. Op. Cit. Page 19
17. Scottsdale Rural/Metro Fire Department "Perspective on Progress." 1993. Page 4.
18. United States Fire Administration. "Residential Fire Sprinkler Retrofit Demonstration Project: Final Report" 1989. Pages 30, 55.
20. Fire Sprinkler Advisory Board of Southern California "1993-Fire Sprinkler Ordinance Survey."