Evaluating Positive Pressure Ventilation In Large Structures: School Pressure and Fire Experiments.
Evaluating Positive Pressure Ventilation In Large
Structures: School Pressure and Fire Experiments.
(15080 K)
Kerber, S.; Madrzykowski, D.
NIST TN 1498; NIST Technical Note 1498; 363 p. July
2008.
Keywords:
ventilation; structures; schools; pressure; experiments;
fans; fuel load; temperature; smoke; visibility;
occupants; uncertainty; smoke spread; scenarios; high
temperature gases; instruments; masonry
Abstract:
A series of experiments was run in a masonry educational
building examining the ability of fire service Positive
Pressure Ventilation (PPV) fans to limit smoke spread or
to remove smoke from areas where potential occupants may
be located. The PPV fans are able to accomplish this by
creating pressures higher than that of the fire to
manage where the smoke and hot gases flowed in the
building. Preliminary experiments examined the pressure
increase created by portable fans and mounted fans in
different configurations and locations. The two main
fire scenarios included a long hallway with classrooms
and a gymnasium. Both scenarios included fires that
produced a large amount of smoke and hot gases, and
instrumentation was placed to assess tenability criteria
and how PPV tactics can either increase or decrease
tenability. Measurements included temperature, pressure,
thermal imaging and video views. In the limited series
of experiments in the long hallways of this masonry
educational building, the use of positive pressure
ventilation to increase pressure to reduce temperatures,
limit smoke spread and increase visibility was
effective. This series of experiments demonstrated that
fire service positive pressure ventilation fans can be
used successfully in large structures to increase
tenability of potential victims and improve conditions
for firefighting crews.
