Quantitatively assessing the effect of exposure time and cooling time of fabric assemblies representative of those used in firefighter clothing on the thermal protection

In addition to direct thermal energy from a heat source, a large amount of thermal energy stored in clothing will continuously transfer to skin during the cooling of fabric assemblies. In real situations, the durations of thermal exposure and cooling in protective clothing vary. Eight exposure times ranging from 6 to 27s and a maximum duration of 80s cooling time were used. To quantitatively investigate the levels of thermal protection, a new index was applied. The effects of exposure and cooling times on the grade of thermal protection were discussed. The effective cooling time was found to be 9-40s for the selected fabric systems. In addition, a safety time region was identified and proposed as an indicator to evaluate the thermal protective insulation of fabric assemblies. The data analyses clearly showed that in addition to the inherent properties of the fabric materials, the levels of protection were not only related to exposure time but also depended upon the cooling time. Copyright (c) 2015 John Wiley & Sons, Ltd.