Investigation of group differences in human perceptions of indoor environment in open-plan offices in a severe cold region

To investigate group differences in human perceptions, long-term and point-in-time measurements on indoor environmental parameters were conducted in 22 open-plan offices in Harbin, China and 1352 questionnaires were collected. The differences in human perceptions among gender, age, level of education, BMI and the location of subjects groups were analyzed. The comfort temperatures for the male subjects were 1.2 °C and 0.8 °C lower than those for the female subjects in summer and winter, which revealed the higher acceptance of female subjects to the higher indoor temperatures. The mean comfort vote for undergraduates was 0.7 higher than those for master and doctoral students in winter. The difference between Griffiths comfort temperatures and operative temperatures in the overweight group was 1.9 °C in summer and 2.5 °C in winter, higher than the normal weight group (1.8 °C and 2.1 °C) and the underweight group (1.3 °C and 1.7 °C), which revealed the lower tolerance of the overweight subjects to higher temperatures than other groups. The subjects who sat near windows had lower thermal comfort votes than the subjects at other locations in all seasons due to solar radiation, radiator heating and the draft caused by window opening. For indoor air quality, sound and light environment, the male subjects had higher comfort votes than those for female subjects, and undergraduates had higher comfort votes than master and doctoral students. Finally, the interaction of five groups on human comfort was also explored. This study can be used to take into account the difference between groups and decide the comfort systems.