Investigation of Indoor Air Quality in the Underground Shopping Mall

Indoor air quality (IAQ) has been a matter of public concern. In the peacetime, a quite number of civil air defense works have been reconstructed to serve for commercial purposes. Good indoor air quality is essential to occupants. In order to characterize the IAQ in underground shopping malls, the IAQ was investigated in an underground shopping mall. The concentration of carbon dioxide (CO₂) is widely used as an indicator of IAQ and ventilation effectiveness. In this paper, the concentrations of CO₂ were investigated, and the indoor temperature and relative humidity were measured. The concentrations of CO₂ in some area of the underground shopping mall exceeded 1500 ppm. The excessive levels of CO₂ could result from high occupancy combined with insufficient ventilation. The influence on the room air environment by introducing internal partitioning was also studied. To assess the IAQ comprehensively, the subjective investigation was conducted with questionnaire survey. The survey revealed that the ventilation should be enhanced to improve IAQ in the underground shopping mall.