Resultant clothing insulation during exercise in the cold.

Predictions of required clothing during work in the cold is often based on data obtained from thermal manikin measurements. These clothing basic insulation values are altered during exercise. In a series of experiments at our laboratory, resultant clothing insulation has been studied. In a cold climatic chamber subjects walked on a treadmill at various exercise intensities dressed in cold protective clothing at different levels of insulation. Thermal insulation of the clothing ensembles was measured with a thermal manikin under standardized conditions. Compared to the standard manikin insulation values, the clothing insulation values measured (resultant insulation) at the human experiments were always lower. Reductions of insulation ranged from 12 to 54% depending on such factors as work intensity, sweating amount, clothing type etc. Predictions of cold protection of clothing at actual use must take into account factors influencing clothing insulation to avoid over-estimation of the cold protective properties of clothing.