Fire Fighting Tactics Under Wind Driven Conditions: Laboratory Experiments.
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.
