Protection and comfort have a complex relation in the development of fire protective clothing. It is one of the major challenges to optimise the fabric structure to get the maximum protection along with the comfort. Thermophysiological comfort is one of them, and it mostly depends on the moisture, vapour and air transmission ability of that fabric.
In this study, meta and para-aramid yarn were blended to develop the outer shell fabrics (OSF) of fire-protective clothing to investigate the moisture transmission properties and the air permeability of OSF. All the fabric samples were manufactured maintaining a constant areal density of around 150 ± 10 gram/m². Physical properties, the OMMC overall moisture management capacity (OMMC), one-way transport capacity and air permeability and other moisture relevant properties were investigated following the ASTM and AATCC standards.
There is significant change in moisture transport properties of from the OMMC value ranged from 0.22 to 0.62. Higher para-aramid content fabrics showed better moisture transport behaviour due to the comparatively more porous structure than the meta-aramid fabrics. Para-aramid fabrics demonstrate enhanced air permeability (about 210 cm³/s/cm²) relative to meta-aramid fabrics (approximately 135 cm³/s/cm²). It is mostly due to the configuration of the para-aramid weave. A negative association was identified between bulk density and thermophysiological comfort; materials with reduced density exhibited significantly greater OMMC and improved ventilation.
The findings suggest that deliberate alterations to fibre composition and density can enhance the breathability and moisture-wicking capabilities of fire-protective fabrics maintaining the protective performance.
