Human health and thermal comfort of office workers in Singapore

Poorly operated air conditioning and mechanical ventilation (ACMV) system might cause significant Sick Building Syndrome (SBS) symptoms and thermal discomfort in the hot and humid climate. This study presents our investigations on the prevalence of SBS symptoms and thermal comfort in offices in Singapore via two approaches including: (1) the onsite objective monitoring and questionnaire-based investigation under normal ACMV practices, and (2) the online survey with occupants in controlled indoor temperatures. The results indicate that the prevalence of individual SBS symptoms is lower than the similar studies in other geographic regions. Overcooling seems to be the domineering complaint in the local context and the occupants seem to prefer higher indoor temperature. As such, human behavioral adjustments such as adding clothing happen quite frequently. Moreover, the data also suggests that cultural traits might skew the survey results, especially in certain subjective aspects regarding the satisfactory level and comfort. To sum up, the prevalence of SBS symptoms are generally acceptable in current local context. However, due to the hot and humid ambient environment, traditional ACMV system with vapor compression refrigerant tends to trigger the overcooling issue in relation to the sensible and latent heat. It is invaluable to advance our understanding of the relationships between the ACMV system, human behavioral adjustments, and building energy consumptions in the tropical region.