Thermal responses and perceptions under distinct ambient temperature and wind conditions

• Relations among wind, thermal perception and human energy balance were studied.
• Human physiological response is a crucial factor for assessing human thermal states.
• Wind speed and direction by themselves do not account for human thermal experience.
• Human thermal load represents skin-temperature regulation as a physiological variable.
• Human thermal load is an accurate indicator of human thermal states under wind.

Wind conditions are widely recognized to influence the thermal states of humans. In this study, we investigated the relationship between wind conditions and thermal perception and energy balance in humans. The study participants were exposed for 20 min to 3 distinct ambient temperatures, wind speeds, and wind angles. During the exposure, the skin temperatures as a physiological reaction and mental reactions of the human body were measured and the energy balance was calculated based on the human thermal-load method. The results indicate that the human thermal load is an accurate indicator of human thermal states under all wind conditions. Furthermore, wind speed and direction by themselves do not account for the human thermal experience. Because of the thermoregulation that occurs to prevent heat loss and protect the core of the body, a low skin temperature was maintained and regional differences in skin temperature were detected under cool ambient conditions. Thus, the human thermal load, which represents physiological parameters such as skin-temperature change, adequately describes the mixed sensation of the human thermal experience.