Newswise — A landmark study coordinated by the National Institute of Standards and Technology (NIST) is the first to put numbers to the effect of changing the size of fire-fighting crews responding to residential fires. Performed by a broad coalition in the scientific, firefighting and public-safety communities, the study quantifies the effects of crew sizes and arrival times on the fire service’s lifesaving and firefighting operations for residential fires. Until now, little scientific data have been available.

The research team found that four-person firefighting crews were able to complete 22 essential firefighting and rescue tasks in a typical residential structure 30 percent faster than two-person crews and 25 percent faster than three-person crews. “The results from this rigorous scientific study on the most common and deadly fires in the country—those in single-family residences—provide quantitative data to fire chiefs and public officials responsible for determining safe staffing levels, station locations and appropriate funding for community and firefighter safety,” says NIST’s Jason Averill, one of the study’s principal investigators.

The four-person crews were able to deliver water to a similar-sized fire 16 percent faster than the two-person crews and 6 percent faster than three-person crews, steps that help to reduce property damage and lower danger to the firefighters. The four-person crews were able to complete search and rescue 30 percent faster than two-person crews and 5 percent faster than three-person crews. Five-person crews were faster than four-person crews in several key tasks. The benefits of five-person crews have also been documented by other researchers for fires in medium- and high-hazard structures, such as high-rise buildings, commercial properties, factories and warehouses.

This study explored fires in a residential structure, where the vast majority of fatal fires occur. The researchers built a two-story, 2,000-square-foot test facility at the Montgomery County Public Safety Training Academy in Rockville, Md. Fire crews from Montgomery County, Md., and Fairfax County, Va., responded to live fires within this facility. NIST researchers and their collaborators conducted more than 60 controlled fire experiments to determine the relative effects of crew size, the arrival time of the first fire crews, and the “stagger,” or spacing, between the arrivals of successive waves of fire-fighting apparatus.

The United States Fire Administration reported that 403,000 residential structure fires killed close to 3,000 people in 2008—accounting for approximately 84 percent of all fire deaths—and injured about 13,500. Direct costs from these fires were about $8.5 billion. Annually, firefighter deaths have remained steady at around 100, while tens of thousands more are injured.

Researchers from NIST, Worcester Polytechnic Institute, the International Association of Fire Chiefs, the International Association of Fire Fighters, the Commission on Fire Accreditation International-RISK and the Urban Institute participated in the study. The report was funded by the U.S. Department of Homeland Security, Federal Emergency Management Agency’s (FEMA) Assistance to Firefighters Grant Program and released today in Washington, D.C., before the start of the annual Congressional Fire Services Institute meeting that draws top fire safety officials from across the nation.

For more details, see the NIST news announcement “Landmark Residential Fire Study Shows How Crew Sizes and Arrival Times Influence Saving Lives and Property,” from April 28, 2010 at www.nist.gov/bfrl/fire_research/residential-fire-report_042810.cfm. The Report on Residential Fireground Field Experiments, NIST Technical Note 1661, can be downloaded from www.nist.gov/cgi-bin/view_pub.cgi?pub_id=904607&division=866.

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