Human skin temperature and thermal responses in asymmetrical cold radiation environments

Many previous studies on human thermal and physiological sensation were done in the box-like chambers which are different from the real environments. The subjects wore summer clothing in the earlier studies which was different from Chinese northern people's clothing in winter. In order to investigate the effect of cold radiation from the outer window on human skin temperature and thermal responses in Harbin winter, a study was carried out in a climate chamber with asymmetrical radiation environments. 20 subjects worn winter clothes participated in the experiments in a chamber with an exterior window which is a more realistic environment in practice. The environmental parameters and skin temperatures were recorded. Meanwhile, the subjects were asked to fill in the questionnaires on five local and overall thermal sensation and thermal comfort. The results show that the cold radiation from the outer window might result in the decreases of local skin temperatures, especially for calf and back. The mean skin temperature is 33.0 °C when subjects felt thermally neutral for the whole body. The results appeared that asymmetrical radiation from the exterior window and clothing has no influence on the preferred mean skin temperature. Overall thermal sensation and mean skin temperature showed a good linear relationship, which showed that human overall thermal sensations may be predicted by their mean skin temperatures. Mean skin temperatures would have less influence on local thermal sensation when local skin temperature was higher than that in neutral condition.