Full-Scale Evaluation of Positive Pressure Ventilation In a Fire Fighter Training Building.
Full-Scale Evaluation of Positive Pressure Ventilation
In a Fire Fighter Training Building.
Kerber, S.; Walton, W. D.
NISTIR 7342; 91 p. July 2006.
fire fighters; fire fighting training; ventilation;
evaluation; experiments; scenarios; uncertainty; tests;
room fires; temperature; oxygen concentration; fuel load
A series of full-scale experiments was conducted in a
three-story fire fighter training burn building to
compare natural ventilation with positive pressure
ventilation (PPV). A wood pallet and dry hay fire was
allowed to burn in the structure with all doors and
windows closed until the fire reached an oxygen-limited
state. A door and window were then opened. The structure
was ventilated naturally or with a positive pressure fan
placed at the front door. Fourteen different
configurations of fire room and vent locations were
examined, each with both natural and positive pressure
ventilation. Gas temperatures, air velocities, fire room
oxygen concentrations and differential pressures were
recorded and compared for the different configurations
and ventilation techniques. The data indicate that, with
both natural and positive pressure ventilation
techniques, using correct ventilation scenarios resulted
in lower temperatures within the structure at the 0.61 m
(2 ft) height, where victims may have been located, and
at the 1.22 m (4 ft) height, where fire fighters may
have been operating. There were only limited ventilation
configurations where the temperatures in rooms other
than the fire room exceeded the victim or fire fighter
threshold temperatures with either ventilation
technique. The use of positive pressure ventilation
resulted in visibility improving more rapidly and, in
many cases, cooled rooms surrounding the fire room.
However, the use of positive pressure ventilation also
caused the fire to grow more quickly, and in some cases,
created higher temperatures at the lower elevations
within the structure. Overall, this limited series of
experiments suggests that PPV can assist in making the
environment in the structure more conducive for