Psychophysical Adaptations to Pre-cooling in Transient Thermal Environments

Abstract

The application of the thermal alliesthesial concept through pre-cooling strategies in tropical buildings has attracted customers by purging surplus body heat, particularly at the entry point of their transitional space. However, there is little empirical evidence on the impact of thermal alliesthesia on the human subject’s perception of sensation and pleasantness. This study aims to investigate this relationship in the thermoneutral zone and various affective responses based on simulated transient thermal environments. Twenty nine healthy college-aged participants are recruited for a series of thermal alliesthesia climate chamber experiments. The predominant ET* setting refers to the participant’s preferred temperature, that is, 25.1 °C (±1.0). Three experiment stages with a total of nine hours, namely, Stage A (predominant ET*: 22 °C), Stage B (predominant ET*: 24 °C), and Stage C (predominant ET*: 26 °C) are devised to simulate the working commute of office workers in and out of an air-conditioning building during warm weather conditions. The results show that a high proportion of participants are indifferent up to 11 °C of down-step despite encountering corrective transitions within the thermoneutral zone. Pre-cooling strategies are not successful in eliciting thermal pleasure responses in any of the three stages. These findings suggest that a preconditioned indoor environment of 24 to 26 °C ET* is thermally sufficient when designing for transient thermal environments, thereby, eliminating the need for over-cooling.