Dynamic thermal responses and showering thermal comfort under different conditions

This study conducted a series of human subject experiments on shower thermal comfort to investigate the dy-namic thermal responses under different conditions. Questionnaires (including thermal sensation votes, thermal comfort votes, sweating sensation votes, and mood-related votes) and physiological parameters (including skin temperature, core temperature, heart rate, blood pressure, and brain waves) were collected from 27 subjects. The results showed that the subjects' comfort-related votes changed dynamically during the pre-, mid-, and post -showering phases. The changes in thermal sensation, thermal comfort, fatigue relieving, and sweating sensa-tion during the 10-min shower were 0.7 +/- 0.8, 0.9 +/- 1.2, 0.9 +/- 1.0, and 0.9 +/- 0.9, respectively. After a 10-min shower, 16 mood-related questions were answered toward positively. The heart rate and mean skin temperature of the subjects increased by approximately 10% and 8%, respectively. The body temperature tended to be more uniform, with smaller temperature differences between the trunk and extremities. The changes in core tem-perature, blood pressure, and brain waves were less significant because the reference test condition (25 degrees C air temperature, 40 degrees C showering water temperature, and 10-min duration) was not intensive. Further analyses indicated showering water temperature and duration were the most significant factors affecting the mid -showering thermal comfort. The ambient temperature and airspeed were the most significant factors affecting post-showering thermal comfort. The initial thermal status primarily affects thermal comfort before showering. No significant difference was observed between the elder and the younger subjects under moderate conditions.