ABSTRACT
Poor Indoor Air Quality as a result of particulate matter (PM) and other gaseous pollutant has received increasing attention from the international environmental scientific community, political institutions, and environmental governances for the depleting effect on the health, and wellbeing of building occupants. This study aims at providing a baseline information on Indoor Air Quality Parameters in classrooms of selected primary schools in Benin City and then establish their compliance with regulatory limits.
Pollutants studied include SPM, PM10, PM2.5, CO and NH3. Particulate matter load were collected during the dry and wet season using standard in-situ air quality sampler such as Casella CEL-712 Microdust Pro Real-time Dust Monitor which measures airborne particulate matters ranging from 0.001 mg/m3 to 250 g/m3. Carbon monoxide levels were measured using a CO dosimeter which measures CO concentrations ranging from 0 to 1000 ppm, with a sensitivity of 1ppm. Ammonia was measured with a handheld meter. The results obtained were subjected to Statistical analysis ANOVA to investigate the seasonal and spatial variation.
The mean PM2.5 concentration in all sampling stations exceeded the 25 μg/m3 and 35 μg/m3 regulatory limits of WHO and USEPA respectively. The mean concentration of SPM, CO and NH3 were all within their available statutory limits. The mean concentration of PM10 in some sampling stations were within the 50 μg/m3 regulatory limit of WHO, while other sampling stations clearly exceeded this limit. Statistically, significant variation (p < 0.05) in the seasonal distributions of the indoor air quality parameters measured in this study was observed. No significant variation (p > 0.05) in the spatial distributions of PM2.5, PM10 and SPM was observed, while significant variation in the spatial distributions of CO and NH3 was observed (p < 0.05). These results revealed that the indoor air quality of the various classroom were influenced by concentrations of outdoor air pollutants, characteristics of the school building, the habits of the occupants and the season of the year.
