Generation of CO in Bench-Scale Fire Tests and the Prediction for Real-Scale Fires.
Generation of CO in Bench-Scale Fire Tests and the
Prediction for Real-Scale Fires.
(966 K)
Babrauskas, V.
Interscience Communications Limited. Fire and
Materials. International Conference, 1st. September
24-25, 1992, Arlington, VA, 155-177 pp, 1992.
Keywords:
carbon monoxide; cone calorimeters; fire hazard;
toxicity; room fires; fire tests; scaling
Abstract:
Carbon monoxide (CO) is the single most important factor
associated with deaths in fires; thus, predictions of CO
developed in fires is an essential aspect of fire
quantification. It is considered crucial to have
correct CO prediction methods for post-flashover fire
stages, since, in the United States at least, the
majority of fire deaths are associated with fires which
have gone to flashover. In this paper, it is shown that
the yields of CO observed in real-scale fires are
generally not related to either the chemical nature of
the material being burned nor to the yield observed for
the same material in bench-scale testing. Instead, the
generation of CO in real-scale fires is determined
largely according to the oxygen available for
combustion, with thermal conditions of the fire plume
also playing a significant role. This behavior is in
sharp contrast to many other material fire properties,
including yeilds of gases such as CO2 and HCl, which can
be predicted for real-scale fires from bench-scale
results. Finally, results from various studies completed
thus far indicate how effective prediction of real-scale
CO yields may be accomplished. While bench-scale
measurements are not necessary to predict real-scale CO,
bench-scale toxic potency measurements can be in error
if the CO component in them does not reflect on the
real-scale CO yield. Thus, a method is developed
whereby the bench-scale toxic potency measurements can
be computationally corrected to better approximate the
toxic potencies measured in real-scale, post-flashover
room fires. These techniques will, undoubtedly, be
further refined as additonal experimental results become
available.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899