Flammability and Dehydration of Painted Gypsum Wallboard Subjected to Fire Heat Fluxes.
Flammability and Dehydration of Painted Gypsum Wallboard
Subjected to Fire Heat Fluxes.
(919 K)
McGraw, J. R., Jr.; Mowrer, F. W.
Fire Safety Science. Proceedings. Sixth (6th)
International Symposium. International Association for
Fire Safety Science (IAFSS). July 5-9, 1999, Poitiers,
France, Intl. Assoc. for Fire Safety Science, Boston,
MA, Curtat, M., Editor(s), 1003-1014 pp, 2000.
Sponsor:
Society of Fire Protection Engineers, Bethesda, MD
Keywords:
fire research; fire safety; fire science; wallboard;
gypsum; flammability; dehydration; heat flux; cone
calorimeters; fire models; flame spread; material
properties
Abstract:
The flammability and dehydration of painted gypsum
wallboard (GWB) exposed to fire heat fluxes are
investigated. Painted GWB samples are subjected to
constant incident heat fluxes ranging from 25 to 75
kW/m2 for periods ranging from 5 to 15 minutes in the
Cone Calorimeter. A number of coats of latex interior
paint, including 0, 2, 4, 6 and 8 coats, are applied
over a single coat of latex primer to the exposed
surface of 15.9-mm (5/8-in.) thick type X GWB. A model
is used to evaluate the potential for flame spread based
on the Cone Calorimeter results. A two-step dehydration
model based on a finite difference formulation is
described for GWB. Experimental results indicate a
distinct dehydration front can be observed by visual
inspection; further analysis is needed to determine the
composition of the GWB on each side of this front.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899