NIST Time|NIST Home|About NIST|Contact NIST

HomeAll Years:AuthorKeywordTitle2005-2010:AuthorKeywordTitle

Heat Transfer Model for Fire Fighter's Protective Clothing.


pdf icon Heat Transfer Model for Fire Fighter's Protective Clothing. (12217 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.