Indoor Environmental Quality of the Workspace and Employees’ Well-being

Abstract

The relationship among environmental and social factors within the built environment and their influence on workers’ wellbeing is emerging as a new line of inquiry. Further, in light of the COVID-19 pandemic, several building standards and certification schemes are now increasing their focus on occupant’s health. Assessing the wellbeing of workers requires more than the traditional focus on measures of the social/managerial environment and include physical attributes of the workspace such as noise, thermal comfort, lighting, and air quality. For this study, the Flourishing Index (FI) assessed employees' complete wellbeing and examined possible associations with the workplace indoor environmental quality (IEQ), as well as effect modifiers and mediators of such association. IEQ sensors installed across office buildings were used for IEQ physical measurements while FI and indoor environmental quality satisfaction (IEQSat) were obtained through online surveys. First, we looked at employees’ IEQSat, IEQ physical measurements, and FI. Participants FI score was significantly associated with IEQSat. Participants FI scores increased approximately 20% for every 1-point satisfaction increase with workspace noise levels, overall air quality, thermal conditions, and natural light. In addition, satisfaction with office air quality decreased as CO2 levels increased (β= -0.169, 95% CI: -0.314, -0.025). Moreover, mediation analysis shows that workspace CO2 concentration has an indirect effect on FI, fully mediated by air quality satisfaction (β= -0.037, 95% CI: -0.078, -0.006). Full mediation or complete mediation is the case in which the exposure no longer affects the outcome variable after controlling for the mediator. Second, we looked at the large shifts in IEQ resulting from work setting changes to detect associations between IEQSat factors and wellbeing in panel data. We analyzed the impact of each IEQSat factor on distinct and comprehensive aspects of wellbeing. To do so, the study used fixed effects models, to control for time-invariant subject characteristics, and FI to assess wellbeing comprehensively. We found that all IEQSat factors are significantly associated with the FI, as well as the domains of “happiness and life satisfaction” (Happiness) and “mental and physical health” (Health). The strongest associations were between the aggregated index for IEQSat and Happiness (β = 0.45, 95% CI: 0.27, 0.64) and the aggregated index for IEQSat and Health (β = 0.41, 95% CI: 0.22, 0.6). Additionally, some IEQSat factors were significantly associated with other domains of FI, such as noise satisfaction with the FI domain of “Close social relationships”. As secondary analysis we explored the moderating effects of socio-demographics on Happiness and Health and found several interacting effects. The highest career levels (6+) modified the effect of noise satisfaction (β = 0.62, 95% CI: 0.11, 1.13) and air quality satisfaction (β = 0.47, 95% CI: 0.04, 0.89). For example, for every 1 unit increase in noise satisfaction, employees in the highest career level increased their FI by an additional .62 points, compared to the lowest career level group (the reference group). Moreover, the association between thermal satisfaction and the Health domain was lower for males (β = -0.41, 95% CI: -0.67, -0.15). Third, the COVID-19 pandemic redefined the spatial and temporal settings of work, forcing a massive shift to work from home. This study drew on data from two company-wide surveys conducted in the fall of 2019 and during the summer of 2021, in Bangkok, Thailand. Survey 1 represented pre-pandemic baseline data from all employees working in different office buildings while survey 2 captured responses from the same employees a year into COVID-19 disruptions, most of them working from home (WFH) and some of them working from the office. We asked employees about IEQSat as well as job resources perception. The mediation analysis results showed that the effect of WFH on wellbeing, as measured with the FI, is fully mediated via noise satisfaction, air quality satisfaction, and sense of belonging at work. In the unadjusted models, the estimate of the natural indirect effect (also referred as indirect effect) of noise satisfaction as a mediator was 0.13 (95% CI: 0.04, 0.26). Air quality satisfaction as a mediator of the association between WFH and FI resulted in an indirect effect of 0.11 (95% CI: 0.03, 0.22). The estimate of the indirect effect for the sense of community at work mediator was marginally significant (significant at the 10% level). Sense of community at work mediated the association between WFH and FI with an indirect effect of 0.05 (95% CI: -0.16, 0.01). Such results show the need to evaluate a comprehensive set of workplace factors when looking at the relationship of work and wellbeing. Future research should focus on a broad set of workplace factors and preferably use a longitudinal approach to detect cause-and-effect relationships.