The thermal properties of a survival bag incorporating metallised plastic sheeting.

Five male subjects were exposed to a cooling environment equivalent to 1082 W/M2. The subjects wore a clothing assembly with insulation properties of 1.55 clo. A casualty bag in corporating metallised plastic sheeting was provided for additional insulation. Deep body temperature fell 1.2 degrees C. and mean skin temperature 2.6 degrees C. over the 2-h period. Metallised plastic sheeting did not prevent heat loss through the clothing assembly, as indicated by the falls in body and skin temperature and an increase in metabolic heat production. From measurements made during the exposure, the calculated insulation value of the complete assembly of 2.93 clo was close to the predicted value of 2.80 clo calculated from the thermal resistance of the assembly layers. It is concluded that the metallised plastic sheeting in this casualty bag did not provide significant additional thermal insulation.