23. Ventilation System Type and the Resulting Classroom Temperature and Air Quality During Heating Season

The present study investigated how different ventilation system types influence classroom temperature and air quality. Five classrooms were selected in the same school. They were ventilated by manually operable windows, manually operable windows with exhaust fan, automatically operable windows with and without exhaust fan and by mechanical ventilation system. Temperature, relative humidity, carbon dioxide (CO₂) concentration and opening of windows were continuously monitored for one month during heating season in 2012. Classroom with manually operable windows had the highest carbon dioxide concentration levels so that the estimated ventilation rate was the lowest compared with the classrooms ventilated with other systems. Temperatures were slightly lower in classroom ventilated by manually operable windows with exhaust fan. Windows were opened seldom even in the classroom ventilated by manually operable windows. Classrooms with automatically operable windows and exhaust fan and with mechanical ventilation systems achieved the best thermal environment and air quality during heating season among all classrooms examined.