Estimates of Thermal Conductivity for Unconditioned and Conditioned Materials Used in Fire Fighters' Protective Clothing .
Estimates of Thermal Conductivity for Unconditioned and
Conditioned Materials Used in Fire Fighters' Protective
Clothing .
(188 K)
Vettori, R. L.
NISTIR 7279; 33 p. November 2005.
Keywords:
protective clothing; fire fighters; thermal
conductivity; heat transfer; test methods; thermal
analysis; uncertainty
Abstract:
Fire fighters' protective clothing provides a limited
amount of thermal protection from environmental
exposures produced by fires. This level of thermal
protection varies with the design, materials,
construction, and fit of the protective garments. Limits
of thermal protection may be analyzed using the
thermophysical properties of garment materials. However,
little information is currently available for analyzing
and predicting protective garment thermal performance.
To address this need, a research effort was begun to
measure the thermal properties of fire fighters'
protective clothing materials. This report presents
thermal conductivity data for ten materials used in
fabricating fire fighters' protective clothing. These
materials included: (a) outer shell fabrics, (b)
moisture barriers, and (c) thermal liner battings. The
thermal conductivity data for each material was obtained
twice. Once when the material was new and once after the
material had undergone a conditioning process of five
washings and dryings by a contract cleaner that
specializes in cleaning, decontaminating and repair of
fire
fighters' protective clothing. The thermal conductivity
of individual protective clothing materials was measured
using the test procedure specified in ASTM C 518
Standard Test Method for Steady-State Thermal
Transmission Properties by Means of Heat Flow Meter
Apparatus.
Measurements producing estimates of thermal conductivity
for a single layer of materials were carried out at mean
test temperatures of 20 DGC (68 DGF), 48 DGC (118 DGF), 55
DGC (131 DGF), and 72 DGC (162 DGF). No visible physical
changes were observed with any of the materials tested
at these temperatures. For unconditioned materials, the
thermal conductivity estimates ranged from 0.034 W/m K
to 0.093 W/m K. For the conditioned materials the
thermal conductivity estimates ranged from 0.033 W/m K
to 0.089 W/m K. Thermal conductivity values increased
for all materials as mean test temperatures were
increased.
