Evaluation of calculation methods of mean skin temperature for use in thermal comfort study

A method was established to evaluate calculation methods of mean skin temperature, in order to find appropriate ones for use in human thermal comfort study. In this method three indexes, including reliability, sensitivity and number of measurement sites, were proposed. Under air temperatures of 21 °C, 24 °C, 26 °C, and 29 °C, 22 subjects’ local skin temperatures (21 sites) and electrocardiograms were measured, and their thermal sensation and thermal comfort were inquired. Human heart rate variability indicated the physiological relation between mean skin temperature and ambient temperature for the sensitivity evaluation. Adopting the evaluation method, 26 types of mean skin temperature calculation methods were evaluated based on the experimental data. The results indicate that a calculation method of mean skin temperature with 10 sites is the most appropriate one, due to its high reliability, excellent sensitivity and fewer measuring sites. When it was applied to reflect thermal comfort, the performance was good.