Effect of stimulation strength of clothing humidity on humidity sensitivity

Abstract

To clarify the effect of clothing humidity on humidity sensitivity, fifteen women subjects entered an experimental chamber in which the chamber humidity increased continuously. The subjects wore three sorts of clothing, semi-nude (shorts and brassiere), cotton underwear (+semi-nude), and polyester underwear (+semi-nude), respectively. Under such conditions, the subjective evaluations (humid sensation, thermal sensation, and comfortable feeling), the measurements of clothing temperature and clothing humidity, and the measurements of the physiological responses (heart rate, oral temperature, and mean skin temperature) were performed. The following results were obtained: 1) The clothing humidity and the humid sensation differed according to the clothing used. 2) The humid sensation related more to the comfort feeling than the thermal sensation. Moreover, there was a higher positive correlation between the humid sensation and the clothing humidity. There were significant correlations between the humid sensation and some physiological responses such as the heart rate, the oral temperature, and the mean skin temperature. 3) The humidity sensitivity increased with the increase in clothing humidity regardless of the sort of clothing used. 4) Dependence of humidity on the apparent differential threshold was higher in semi-nude, and, in contrast, lower in the cotton underwear. However, the apparent differential threshold in the high humidity region ranged between 4 % and 6% in relative humidity regardless of the sorts of clothing.