Five classrooms in Hong Kong (HK), air-conditioned or ceiling fans ventilated, were chosen for investigation of indoor and outdoor air quality. Parameters such as temperature, relative humidity (RH), carbon dioxide (CO2), sulphur dioxide (SO2), nitric oxide (NO), nitrogen dioxide (NO2), respirable particulate matter (PM10), formaldehyde (HCHO), and total bacteria counts were monitored indoors and outdoors simultaneously. The average respirable particulate matter concentrations were higher than the HK Objective, and the maximum indoor PM10level exceeded 1000 μg/m3. Indoor CO2concentrations often exceeded 1000 μl/l in air-conditioning and ceiling fan classrooms, indicating inadequate ventilation. Maximum indoor CO2level reached 5900 μl/l during class at the classroom with cooling tower ventilation. Increasing the rate of ventilation or implementation of breaks between classes is recommended to alleviate the high CO2level. Other pollution parameters measured in this study complied with the standards. The two most important classroom air quality problems in Hong Kong were PM10and CO2levels.
ASJC Scopus subject areas
- Environmental Chemistry