Abstract
Recent improvements in the hardware performance of telecommunication machines have allowed higher air temperature atmosphere. However, workers for maintenance must feel thermal discomfort under such a moderate heat stress. To alleviate it, new two types of cooling vests, "Cotton" and "Mesh", were designed and proposed in this paper. Subjective experiments were conducted to evaluate the effect of proposed cooling vests. Four college-age male subjects and four middle-age male subjects were participated in the wear trial test. The chamber was conditioned at operative temperature of 30.2℃, relative humidity of 39%RH, and still air. By wearing new developed cooling vests, comfort sensations were closer to the neutral conditions. From comfort sensation votes it was estimated to be equal to about 1.5℃ decrement of operative temperature. Among college-age-subjects there were no significant difference in thermal sensations, but among middle-age-subjects there were the cooling effects of about 2℃ decrement of operative temperature for forty minutes. By wearing our cooling vests, the relative humidity under clothing was decreased and the sweating sensation value with the cooling vest was smaller than Control condition. The evaporative heat loss from skin with our cooling vests was about 53.5W/m^2. This value was smaller than Control condition of 68.3W/m^2.
