Office thermal environment that maximizes workers’ thermal comfort and productivity

Previous studies investigating the relationship between indoor environmental quality and worker productivity have suggested that thermal environment has a significant impact on worker productivity. Some of these studies reported that productivity was less than optimal when the environment was thermally neutral and comfortable (i.e., PMV = 0.0). However, the analyses in those studies did not consider personal attributes, and the data hierarchy resulting from the multiple responses of survey participants was also not considered. Thus, there is no consensus on the optimal temperature for worker productivity. In this study, a measurement survey and questionnaire survey were conducted to assess worker productivity in a thermally neutral and slightly cool environment while considering the personal attributes of workers. The survey was conducted with air conditioning set to PMV = 0.0 and −0.5 for 2 weeks during late spring in Tokyo, Japan. The results of a multilevel analysis considering data hierarchy revealed that the relationship between thermal sensation and productivity differed according to gender. Men were most productive when it was cooler than thermally neutral (thermal sensation = −0.61, between “−1. slightly cool” and “0. neutral”), while women were most productive when it was warmer than thermally neutral (thermal sensation = 0.23, between “0. neutral” and “1. slightly warm”). The relationship between thermal satisfaction and productivity suggests that there may be a difference in thermal sensation that maximizes productivity and thermal satisfaction. This study provides new knowledge regarding the office thermal environment that maximizes worker productivity and thermal satisfaction.