Effects of thermal history on human thermal adaptation to central heating environments in severe cold zone

A field investigation is carried out on the indoor thermal and humidity environment of a university building and the subjects’ thermal and humidity responses during winter heating in Harbin,and a total of 495 valid questionnaires are collected.The subjects are divided into groups according to their duration of living in the central heating environment in the northern severe cold zone,and the differences in thermal and humidity responses and the adaptability of people with different thermal histories are analysed.The results indicate that with an increase in the duration of living,the proportion of individuals reporting the thermal sensation lower than “neutral” and the “neutral” humidity sensation increases obviously.The mean thermal sensation vote for individuals with one year of thermal histories in the north is 0.6,and it decreases with the residential duration increasing.The individuals living in a comfortable and warm central heating environment for a long period raise their thermal expectations and requirements for environments.The participants without any thermal histories in the north take a maximum of one year to adapt to the central heating environment,but they require three years to adapt to the humidity environment.The thermal neutral temperature for the individuals living in the north for less than one year is 18.6 ℃,while it is 18.9 ℃ for the people living there for more than one year.After correcting the clothing insulation,the difference in thermal neutral temperature between them is 0.5 ℃.