A survey of high school students' clothing in classroom

In this study, a thermal-environment survey focusing on clothing behaviors of students in high-school classrooms was performed during summer. Subsequently, statistical analysis was performed to estimate the realizable limit level of adaptation to the thermal environment by adjusting clothing behavior. Additionally, a questionnaire-based subjective-vote and thermal-environment surveys were conducted in a naturally ventilated high school in Nagano city, Japan, during summers of 2017 and 2018. Nagano city is characterized by a humid subtropical climate (Cfa), per Koppen climate classification. The study involved 59 male and 21 female participants aged between 15 and 18 years. Five hundred and two subjective votes were collected in this study with 365 and 137 votes being cast by male and female participants, respectively. The average outdoor air temperature measured 23.9 degrees C during the survey period, whereas the average indoor operative temperature equaled 28.0 degrees C. The insulation level of clothing worn by participants varied in the 0.29-0.77 do range. Results of regression analysis reveal that both male and female participants reduced their clothing insulation level in response to an increase in indoor operative temperature. However, at operative temperatures exceeding 29 degrees C, the median value for clothing insulation was observed to be in the 0.31-0.37 do range. This result reveals limitations that exist with regard to clothing adjustments that can be made by participants in hot environments. Additionally, thermal sensation votes were observed to increase at operative temperatures exceeding 29 degrees C, thereby confirming the existence of a limit to thermal-environment adaptation realizable via adjustment of clothing insulation levels.