Main Article Content
Indoor air quality directly affects the health of the occupants of the building. Since many people spend an average of 90 % of their days in buildings, it is important to monitor indoor air quality. This research aimed to monitor the indoor air quality of some classrooms of the Department of Environmental Science, Faculty of Science and Technology, Chiang Mai Rajabhat University. Physical factors (temperature, relative humidity, illuminance, and room-users), chemical factor (carbon dioxide concentration), and biological factors (bacteria and fungi concentration values) were recorded. Microorganisms were sampled using an air sampler MAS100 NT® (MERCK). Indoor air quality was monitored between October and November. Samples were collected in the morning and afternoon twice a week on Monday and Wednesday. The factors affecting indoor air quality were analyzed. The results revealed that the air quality in the classrooms often exceeded safe standards in terms of temperature, relative humidity, carbon dioxide gas and the number of bacteria. However, the degree of illuminance in both classrooms was found to be within the standard. There was a positive correlation between the number of bacteria, carbon dioxide concentration and the number of people in the room. Therefore, improvement in air quality should be initiated by the installation of exhaust fans and the regular cleaning air conditioner units. In addition, indoor air quality of intensively used areas should be frequently monitored.
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