A field survey on indoor air pollution in school classrooms with different ventilation methods

The purpose of this study was to investigate the actual indoor air quality within two elementary schools with different types of ventilation methods, and to obtain data pertaining to the emission of bioeffluents within the schools. Field surveys on indoor air quality were conducted at two public elementary schools in Tokyo, both equipped with air-conditioning systems. School-A was also equipped with a heat-exchange ventilation system, while School-B did not have a ventilation system. Results of the study revealed that the target ventilation volume for the heat-exchange ventilation system in School-A was not achieved, indoor air quality in School-B was better in relatively cool conditions than School-A because of the habit of opening windows attached, there was a positive correlation between nonanal and decanal and CO2 concentration in summer, and the concentration of bioeffluents nonanal and decanal may be higher at high temperatures even under the same level of ventilation.