Air conditioner operation behavior based on skin temperature in a classroom

Abstract

A total of 25 college students participated as subjects to elucidate when they turned ON/OFF the air-conditioner based on thermal environment and skin temperature. During they participated in a lecture in which a package air-conditioner installed in the class room, the ambient temperature and relative humidity were measured at 75cm above floor every minute. Skin temperatures were measured every minute at 7 points according to the Hardy and Dubois recommendation; the fore head, right abdomen, left outer mid lower arm, left hand, right anterior thigh, right shin and right instep. When they turned ON/OFF air-conditioner the ambient temperature, relative humidity and mean skin temperature was 27.4°/23.7°C (p=0.000), 40.9%/40.0% (p=0.528) and 32.7°/32.1°C (p=0.024), respectively. When the air conditioner was tuned ON and OFF, the difference in the head- (34.45±S.D1.25°C / 34.31±0.97°C), abdomen- (33.77±1.66°C / 33.57±1.667°C) and thigh-skin temperature (32.31±1.31°C / 31.70±1.77°C) was statistically not significant, however, in the mid lower arm- (31.20±1.11°C / 30.47±1.58°C), hand- (31.58±1.80°C / 30.71±2.05°C), shin-(31.88±1. 14°C / 30.92±1.23°C) and instep-skin temperature (33.27±1.33°C / 32.50±1.77°C), the difference was statistically significant, respectively. The indoor ambient temperature of a class room is recommended to be fluctuating in the range of 23.7-27.4°C to archive comfortable and healthy environment.