Lighting and thermal factors on human comfort, work performance, and sick building syndrome in the underground building environment

The development of underground space can help cities solve problems such as the unmet demand for land and space. However, there are still many problems to be solved. The comfort of lighting and thermal environment, high work performance, and low prevalence of SBS symptoms play irreplaceable roles in creating a good indoor environment. The main purpose of this study is to investigate the differences in the comfort of lighting and thermal environment, work performance, and SBS symptoms among people living in underground spaces for long and short periods, and to provide optimal temperature and illuminance ranges for balancing these three aspects. A summer survey was conducted in subway stations, including measurements of environmental and physiological parameters, and psychological responses. A total of 952 questionnaires were collected for data analysis. The results show that the comfort of lighting and thermal environment for short-stay occupants is more sensitive to changes in indoor air temperature and illuminance. Reduction of indoor air temperature can improve occupants’ work performance and can reduce SBS symptoms. The optimal temperatures for long-stay and short-stay occupants are 25.6–26.3 °C and 24.5–24.8 °C (or 24.5–25.1 °C), respectively. The optimal illuminance ranges for long-stay and short-stay occupants are > 300.0 lx and > 494.0 lx, respectively. The results of this research contribute to the creation of healthy, comfortable, and beneficial indoor environments in shared underground building spaces. [Display omitted] •Short-stayers were more sensitive to changes in temperature and illuminance.•Reducing the temperature properly could improve work performance.•Long-stayers showed more obvious Sick Building Syndrome symptoms.•The comfort ranges for long-stayers were 25.6–26.3 °C and > 300.0 lx.•The comfort ranges for short-stayers were 24.5–24.8 °C and > 494.0 lx.