Effects of heat radiation on the heat exchange with protective clothing - a thermal mankin study

Within the scope of the European research initiative THERMPROTECT numerous thermal manikin experiments were performed on the transfer of heat through personal protective clothing (PPC) under far infrared radiation (FIR) stress. The influence of the reflectivity and insulation of the clothing, the radiated body surface area, and the interaction with convection and wet underwear were considered. The data showed a decrease in whole body heat loss, i.e. heat gain under radiant heat stress. This heat gain increased with radiation intensity, the slope depending on air velocity and underwear insulation. Except for an aluminised garment that showed minor effects, the influence of the material and colour of the outer layer was negligible, as was the effect of radiation geometry. However, wetted underwear caused differential effects, with FIR induced heat gain depending on water vapour permeability.