Comparing the Performance of Residential Fire Sprinklers with Other Life Safety Technologies
David T. Butry
Residential fire sprinklers have long proven themselves as life safety technologies to the fire service community. Only until recently have they shown to be cost-effective for homeowners, as installation costs have fallen and performance increased. While it has been demonstrated that residential fire sprinklers yield reductions in fatalities, injuries, and property damage using a national statistics approach, it has been suggested that the performance may be inflated. A national statistics approach, it is argued, may ignore underlying differences between sprinklered and non-sprinklered homes related to structural characteristics, construction materials, demographical factors, and the presences of other fire safety technology. Propensity score matching techniques, commonly employed in labor economics and epidemiology to measure the effects of programs and treatments, facilitates comparisons between treated units (e.g., sprinklered homes) with similar untreated units (e.g., non-sprinklered homes). Matching is conducted over a set of covariates known to affect both treatment status and treatment performance, thereby eliminating the effects of confounding factors. In this analysis we conduct a community-level examination of sprinkler performance by comparing like structure fires in one- and two-family dwellings, while conditioning on fire detection technology and neighborhood housing and socioeconomic conditions, using propensity score matching. We estimate residential fire sprinkler performance to be similar to that reported using a national statistics approach; however, we find that differences do exist between sprinklered and non-sprinklered homes, so care should be given when comparing sprinkler performance at the community level. Results show that hardwired smoke alarms are superior to those powered only by batteries, but that fire sprinklers still provide an additional level of life safety. Finally we find that the economic returns to sprinkler use are greater in absolute and per-event terms than current automotive air bag technologies, which have been mandated for use nationwide in passenger vehicles since 1998. For homeowners of sprinklered homes, the likelihood of being saved by a sprinkler in a fire is greater than being saved by an air bag in a vehicle crash.