Heat Transfer Model for Fire Fighter's Protective Clothing.
Heat Transfer Model for Fire Fighter's Protective
Clothing.
(2130 K)
Mell, W. E.; Lawson, J. R.
NISTIR 6299; FA 192; 33 p. January 1999.
Fire Technology, Vol. 36, No. 1, 39-68, February, 1st
Quarter, 2000.
Available from:
National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
Telephone:
1-800-553-6847 or 703-605-6000;
Fax: 703-605-6900.
Website: http://www.ntis.gov
Order number: PB99-134702
Keywords:
protective clothing; fire fighters; heat transfer;
turnout coats; thermal insulation; fire research;
computer models
Abstract:
An accurate and flexible model of heat transfer through
fire fighter protective clothing has many uses. The
degree of protection, in terms of burn injury and heat
stress, of a particular fabric assembly could be
investigated. The expected performance of new or
candidate fabric designs or fabric combinations could be
analyzed cheaply and quickly. This paper presents the
first stage in the development of a heat transfer model
for fire fighters' protective clothing. The protective
fabrics are assumed to be dry (e.g., no moisture from
perspiration) and the fabric temperatures considered are
below the point of thermal degradation (e.g., melting or
charring). Many burn injuries to fire fighters occur
even when there is no thermal degradation of their
protective gear. A planar geometry of the fabric layers
is assumed with one-dimensional heat transfer. The
forward-reverse model is used for radiative heat
transfer. The accuracy of the model is tested by
comparing time dependent temperatures from both within
and on the surface of a typical fabric assembly to those
obtained experimentally. Overall the mode1 performed
well, especially in the interior of the garment where
the temperature difference between the experiment and
simulation was within 5 deg C. The predicted temperature
on the outer shell of the garment differed most from
experimental values (by as much as 24 deg C). This was
probably due to the absence of fabric-specific optical
properties (transmissivity and reflectivity) used for
mode1 input.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899