Examining the indirect effects of indoor environmental quality on task performance: The mediating roles of physiological response and emotion

Most studies have been conducted on the impact of indoor environmental quality (IEQ) on occupants' task performance. However, most studies are based on the assumption that IEQ directly affects task performance. Different hypotheses have been proposed that contradict this conventional belief. The objective of this study is to examine the indirect effects of IEQ on task performance. To identify unknown mediating variables between IEQ and task performance, two research hypotheses were set up: (i) Emotion is the result of a physiological response change in the body and would be influenced by the IEQ in the built environment; and (ii) Task performance would be influenced by IEQ-evoked emotion of occupants. The partial least squares structural equation modeling (PLS-SEM) was employed to verify two interrelated research hypotheses and conduct mediating effect analysis using SmartPLS 3.3.1. The results of this study demonstrated the following: (i) IEQ has no direct effect on task performance but has an indirect effect mediated by dominance resulting from skin conductance; (ii) hot and humid thermal environment and unpleasant indoor air quality increase human skin conductance, which in turn leads to passive emotions. The passive emotions that are not under direct human control result in the degradation of task performance. Using the findings of this study, future smart offices need to collect human bio-signals and emotions and manage IEQ based on these data unlike past smart offices that considered only environmental factors.