Characteristics of Fire Scenarios in Which Sublethal Effects of Smoke Are Important.
Characteristics of Fire Scenarios in Which Sublethal
Effects of Smoke Are Important.
Peacock, R. D.; Averill, J. D.; Reneke, P. A.; Jones, W.
Fire Technology, Vol. 40, No. 2, 127-147, April 2004.
compartment fires; fire models; incapacitation; smoke;
toxicity; scenarios; heat release rate; gas yields;
computer models; geometry
A number of simulations were performed using the CFAST
zone fire model to predict the relative times at which
smoke inhalation and heat exposure would result in
incapacitation. Fires in three building types were
modeled: a ranch house, a hotel, and an office building.
Gas species yields and rates of heat release for these
design fires were derived from a review of real-scale
fire test data. The incapacitation equations were taken
from draft 14 of ISO document 13571. Sublethal effects
of smoke were deemed important when incapacitation from
smoke inhalation occurred before harm from thermal
effects occurred. Real-scale HCl yield data were
incorporated as available; the modeling indicated that
the yield would need to be 5 to 10 times higher for
incapacitation from HCl to precede incapacitation from
narcotic gases, including CO COd2, HCN and reduce O2.
The results suggest that occupancies in which sublethal
effects from open fires could affect escape and survival
include multi-room residences, medical facilities,
schools, and correctional facilities. In addition, fires
originating in concealed spaces in any occupancy pose
such a threat. Sublethal effects of smoke are not likely
to be of prime concern for open fires in single- or
two-compartment occupancies (e.g., small apartments and
transportation vehicles) themselves, although sublethal
effects may be important in adjacent spaces; buildings
with high ceilings and large rooms (e.g., warehouses,
mercantile); and occupancies in which fires will be
detected promptly and from which escape or rescue will
occur within a few minutes.