Transport of High Concentrations of Carbon Monoxide to Locations Remote the Burning Compartment. Annual Report. September 1, 1995-August 31, 1996.
Transport of High Concentrations of Carbon Monoxide to
Locations Remote the Burning Compartment. Annual
Report. September 1, 1995-August 31, 1996.
(31019 K)
Lattimer, B. Y.; Vandsburger, U.; Roby, R. J.
NIST GCR 97-713; 349 p. April 1997.
Sponsor:
National Institute of Standards and Technology,
Gaithersburg, MD
Available from:
National Technical Information Service
Order number: PB97-167563
Keywords:
carbon monoxide; compartments; ceiling jets; corridors;
exhaust gases; fire behavior; room fires; stoichiometry;
combustion gases; toxic products
Abstract:
An experimental study was conducted to measure the
effects of oxygen entrainment on the transport of CO in
building fires, and to develop a procedure for
estimating CO levels during a building fire.
Experiments were performed with an insulated 1/4-scale
room connected to the side of a 1/4-scale hallway
forming a L-shape. Measurements of CO, unburned
hydrocarbons (UHC), CO2 and O2 concentrations and
temperature were performed within the compartment, the
hallway and post-hallway in the exhaust duct. The level
of CO transported to remote locations from the burning
room was hypothesized to be most significantly affected
by the oxygen entrainment into the compartment fire
gases entering the hallway. With a fixed size opening
connecting the compartment to the hallway, the oxygen
entrainment was varied by changing the depth of the
oxygen deficient hallway upper-layer. In experiments
where compartment fire gases entered the hallway
completely surrounded by oxygen deficient combustion
gases, post-hallway CO yields were measured to be as
much as 23% greater than CO yields measured inside the
compartment, despite the presence of external burning.
With deep upper-layers in the hallway, geometric effects
were not observed to significantly affect the
transported level of CO. Instead, the CO level was a
function of the compartment stoichiometry and the
occurrence of external burning.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899