Heat-Transfer Properties of Ten Underwear—Outerwear Ensembles

The heat-transfer properties of 10 underwear-outerwear ensembles were determined in the laboratory by using a heated "sweating" sectional manikin. Theoretically, by applying the i_m theory to these results, a Nomex underwear-Nomex outerwear ensemble showed a slightly greater environmental range. However, little differences were found in the indi vidual clo or i_m clo values among the underwear combinations. The results for two ensembles having the same under wear but different outerwear indicated that the outerwear could be the deciding factor in determining the thermal char acteristics of complete clothing ensembles. It appears that underwear per se merely occupies a portion of the still air layer, and, therefore, the nature of underwear has little to do with the over-all thermal insulation, although these results may be independent of subjective comfort.