Skin Temperature in Relation to the Warmth of the Environment

Abstract

The skin temperatures of industrial workers, mainly women and girls, engaged in very light occupations, have been correlated with environmental conditions. The temperatures of the forehead and of the palm of the hand were measured with a Moll radiation thermopile, and for the temperature of the foot a thermo-junction was used. Altogether 3085 sets of observations were made.Various measures of environmental warmth (dry-bulb air temperature, equivalent temperature, effective temperature, and dry kata cooling power) were correlated with skin temperature. The dry-bulb air temperature is about as good an index of skin temperature as any of the other measures used, while it appears that skin temperature may be slightly less closely associated with dry kata cooling power than with the other measures of warmth conditions.At an average air temperature of 18° C., the average skin temperatures observed were: on the forehead 34·25° C.; on the palm of the hand 29·2° C.; and on the foot 24·4° C. The average increases in skin temperature for a rise of 1° in air temperature were: on the forehead 0·139°; on the hand 0·465°; and on the foot 0·806° C.There was much variation in the skin temperatures recorded at any particular air temperature. The root-mean-square errors of estimation of skin temperature from air temperature were 0·81, 2·51, and 2·80° C., for the forehead, hands and feet respectively.Correlations between the temperatures of different areas of skin were rather lower than those between air and skin temperature.