Classroom indoor air quality and its association with sick Building syndrome (SBS) symptoms in a Malaysian university setting

This study aimed to investigate the association between indoor air quality (IAQ) parameters and the prevalence of Sick Building Syndrome (SBS) symptoms among university students in different types of classrooms. The research responds to growing concerns about environmental health risks in educational settings and seeks to identify key IAQ predictors of SBS symptoms. A cross-sectional study was conducted among 205 students at a Malaysian public university. An online questionnaire adapted from the Indoor Air Quality Industry Code of Practice (ICOP-IAQ) 2010 was used to assess SBS symptoms. Simultaneously, IAQ monitoring was carried out in selected lecture halls (LHs) and tutorial rooms (TRs) using calibrated instruments to measure PM 2.5 , PM 10 , temperature, relative humidity, carbon monoxide (CO), carbon dioxide (CO 2 ), total bacterial count, and fungal count. Comparisons were made between the classrooms. Significant differences were observed between LHs and TRs for PM 2.5 , PM 10 , temperature, relative humidity, CO, and bacterial counts. SBS symptoms were more prevalent in LHs (70.2%) than in TRs (56.6%). In LHs, CO, PM 10 , relative humidity, and fungal count were significantly associated with SBS symptoms, while in TRs, only CO 2 showed a significant association. Multivariate analysis identified CO, PM 10 , and fungal count as significant predictors in LHs (AOR = 4.7; p < 0.001), and CO 2 in TRs (AOR = 2.7; p = 0.003). IAQ parameters are significant contributors to SBS symptom prevalence among university students, with differences influenced by classroom type and ventilation design. These findings emphasize the urgency of IAQ interventions in academic institutions.