Effects of daytime cool vs warm exposure on evening thermal perception and thermoregulation

Abstract

Thermal conditions experienced during daytime can be different from those experienced after working hours outdoors or at home. Since most dwellings in Central and Western Europe in the temperate climate zone are naturally ventilated (NV), while public spaces and offices are often air conditioned (AC), a substantial gap between daytime and evening thermal exposure can occur. This thermal gap likely reduces acclimation to the more ‘natural’ climate outdoors and in NV spaces, and therefore may affect thermoregulation and thermal perception. Structural information on how thermal conditions experienced during daytime (e.g. in offices) influence thermal perception and physiology in the evening (at people’s private homes). Therefore, the present study seeks to assess the impact of staying in cool vs. warm environments during daytime working hours on thermal perception and thermophysiology in the evening at home. In this hybrid laboratory and field study, 31 participants (41±17 years, BMI: 24±3 kg/m2) were exposed to a simulated workday in either 21 ˚C (cool) or 28 ˚C (warm) at two separate occasions. Thermal sensation, thermal preference and mean skin temperature were measured at eight timepoints throughout the day (lab) and evening (home) until the following morning. Preliminary results suggest that daytime thermal conditions affect people’s thermal perception and thermophysiology after working hours at home. The effect is most pronounced just after arriving at home and decreases over time. Importantly, our results raise the question whether conditioning of work places solely based on on-site productivity and comfort, but without considering the impact on comfort and well-being during leisure and recovery time at home, is the way to go in the future.