NIST Time|NIST Home|About NIST|Contact NIST

HomeAll Years:AuthorKeywordTitle2005-2010:AuthorKeywordTitle

Fire Fighting Tactics Under Wind Driven Conditions: Laboratory Experiments.


pdf icon Fire Fighting Tactics Under Wind Driven Conditions: Laboratory Experiments. (11776 K)
Madrzykowski, D.; Kerber, S. I.

NIST TN 1618; NIST Technical Note 1618; 413 p. January 2009.

Sponsor:

Fire Protection Research Foundation, Quincy, MA
U.S. Department of Homeland Security, Washington, DC

Keywords:

fire fighting; wind effects; experiments; heat release rate; structures; uncedrtainity; instruments; upholstered furniture; chairs; couches; fuel load; pressure; wind velocity; water spray; water; pressure; temperature; heat flux; velocity; doors; test methods; living rooms; fire protection; fire spread; oxygen; carbon dioxide; hydrocarbons; carbon monoxide; corridors; apartments; flashover; fire fighters; occupants; fire suppression; fire hoses

Abstract:

The National Institute of Standards and Technology, with the support of the Fire Protection Research Foundation and the U.S. Fire Administration conducted eight fire experiments to examine the impact of wind on fire spread through a multiroom structure and examine the capabilities of wind-control devices (WCD) and externally applied water to mitigate the hazard. The measurements used to examine the impact of the WCDs and the external water application tactics were heat release rate, temperature, heat flux, and gas velocity inside the structure. Measurements of oxygen, carbon dioxide, carbon monoxide, total hydrocarbons and differential pressures were also measured. Each of the experiments was recorded with video and thermal imaging cameras. The experiments were designed to expose a public corridor area to a wind driven, post-flashover apartment fire. The door from the apartment to the corridor was open for each of the experiments. The conditions in the corridor were of critical importance because that is the portion of the building that firefighters would use to approach the fire apartment or that occupants from an adjoining apartment would use to exit the building. The fires were ignited in the bedroom of the apartment. Prior to the failure or venting of the bedroom window, which was on the upwind side of the experimental apartment, the heat realease rate from the fire was on the order of 1 MW. Prior to implementing either of the mitigating tactics, the heat release rates from the post-flashover structure fire were typically between 15 MW and 20 MW. When the door from the apartment to the corridor was open, temperatures in the corridor area near the open doorway, 1.52 m (5.00 ft) below the ceiling, were in excess of 600DGC (1112DGF) for each of the experiments. The heat fluxes measured in the same location, during the same experiments, were in excess of 70 kW/m2. These extreme thermal conditions are not teneable, even for a firefighter in fully protective gear. These conditions were attained within 30s of the window failure.In these experiments, the WCDs reduced the temperatures in corridor outside the doorway by more than 50% within 60s of deployment. The heat fluxes were reduced by at least 70% during this same time period. The WCDs also mitigated completely any gas velocity due to the external wind.