Study on the evaluation of outdoor thermal comfort for elderly people: a case study of Chengdu, China

Population aging has become a prevalent global phenomenon. Comfortable outdoor spaces can promote good health for the elderly. This paper aimed to investigate the effect of environmental parameters of hot summer and cold winter climate area on outdoor thermal comfort for the elderly during summer, transition season, and winter. Two urban parks in Chengdu, China, were selected as the research sites. Microclimate measurements and subjective thermal sensory questionnaire was administered to 602 participants. The thermal sensation, thermal neutral Physiological Equivalent Temperature (PET), and comfort PET range were calculated and analyzed. The associations between thermal sensation and environment parameters were explored by using regression model. The following results can be concluded. (1) Elderly are more sensitive to the thermal environment in summer than in winter. The mean radiation temperature (Tmrt) is the most important variables for elderly in summer. While in winter the relationship between thermal environmental parameters and thermal sensation was not significant. (2) The outdoor neutral PET is 24.56°C, 16.78°C and 15.01°C in summer, fall, and winter, respectively. The neutral PET is higher than that of elderly in cold climate area. (3) During summer, old adults preferred a lower Tmrt and higher wind speed. In fall, old adults preferred higher humidity and lower air temperature.