Study on the influence of constructional parameters on performance of outer layer of thermal protective clothing

Abstract

A study was designed to determine the effect of basic construction parameters of woven fabric on the thermal protection and comfort performance of the fabric. Thermal protection performance may be calculated using thermal protective performance (TPP) rating. The thermal resistance and water vapour transmission rate (WVTR) of different fabric woven patterns were used to evaluate their comfort performance. The current research is primarily concerned with determining the influence of fabric weaving pattern (plain, twill 2/2, twill 3/1, satin and honeycomb), picks per inch (40, 50 and 60), ply of yarn (2 ply and 3 ply) and type of material (meta aramid and para aramid). We measured the TPP rating of fabrics against 50:50 combination of radiant heat and flame exposures at high level of heat flux (80 ± 2 kW/m2 or ∼2 cal/cm2/s). It was found that the TPP rating of honeycomb weave was very good for the same picks per inch compare to other weaves. The change in ply of yarn (from 3 ply to 2 ply) reduce the TPP rating and areal density of fabric but % loss in areal density is higher compare to TPP rating. Comparing honeycomb woven fabrics to fabrics with different weaving pattern, thermal resistance of honeycomb woven fabrics were good. As the number of fabric picks per inch increased for each type of woven structure examined, the TPP rating and thermal resistance improved, while WVTR declined. The multiple linear regression equation (model) is significant for TPP rating.