Cooling Method for Preventing Heat Strokes in Hot Environments

Abstract

In this study, to develop a simple and practical cooling method for hot environments, a vest was designed by incorporating a highly absorbent batting material and a moisture-permeable and waterproof fabric as the cover fabric. The authors have named this vest as the “cooling vest.” Three types of clothing styles were examined: T-shirts （sample T）， T-shirts and a jacket with two small fans （sample TA）， and T-shirts, the cooling vest, and a jacket with two small fans （sample TVA）．Five female subjects aged 21-27 years were engaged for the study. The experiments were performed in an environment having a temperature of 32℃．Following parameters were measured through the wearing experiments: sweating rate, clothing temperature and humidity, oral temperature, skin temperature, and heart rate. Obtained results indicate that compared to the other samples, skin temperature, clothing temperature, and sweating rate tend to be lower in the case of sample TVA. The effect of sample TVA on heart rate and oral temperature could not be observed because the duration of wearing time was very short （15 min）．Additionally, subjective evaluation suggests that sample TVA is comfortable to wear and feels cool. These results can be attributed to the release of water vapor from the cooling vest and enhanced evaporation caused by the fans. Furthermore, while conducting the wearing experiments, clothing humidity increased owing to the evaporation of water vapor from the cooling vest, but the corresponding evaluation score for humid sensation didn't decrease. Hence, it can be concluded that by employing the cooling vest along with a jacket having fans, the loss of latent heat can be increased without causing excessive sweating.