Investigation of the relationships between thermal sensations of local body areas and the whole body in an indoor built environment

This study investigated the relationship of thermal sensations of local body segments and the whole body for a better understanding of how to estimate the overall thermal perception, as a function of partial body sensations, while considering human factors such as gender and body mass index. Thermal comfort, which can be expressed as a function of thermal dynamics between the human body and ambient thermal conditions, primarily consists of a combination of local thermal perceptions. An individual body area contributes to an overall thermal sensation at different significance levels, so that specific areas have high potential for determining the whole-body sensation. This is especially true in a typical building environment where thermal conditions are uniformly distributed and no extremely cold or hot condition occurs. For this study, a series of human subject experiments was conducted with 18 volunteers in an environmental chamber, while thermal conditions changed and thermal sensations were surveyed in the regular way. Seven local body areas were selected, based on current thermoregulation-related literature, and their local body sensations were recorded together. This study revealed that each local body sensation significantly correlated with the overall sensation, but that whole-body sensations varied for each individual body area. In addition, results of this research also suggested optimal combinations of local body areas that could represent the whole-body sensation with a high degree of accuracy.