INDOOR AIR QUALITY AND THE ADEQUACY OF CLEANING IN 25 FINNISH SCHOOLS

摘要

Indoor air quality and the adequacy of cleaning were studied in 25 schools in a Finnish city. Methods included a questionnaire for teachers (Oerebro MM-40-FIN) and measurements of ventilation rate, CO_2, temperature, particulate matter (PM) and surface dust in 56 classrooms. In most classrooms, ventilation rates did not fulfill the rate required by the Finnish building code. CO_2 concentrations were lowest in classrooms with mechanical ventilation and highest in classrooms with natural ventilation. Ventilation rates correlated with PM in all particle size groups except the smallest one. Total PM-levels exceeded the recommended values, and almost all classrooms were too warm. No correlation was found between PM and surface dust. According to the questionnaire (n=424 teachers), main problems in the working environment were dust, stuffy or dry air and noise. There was a statistically significant correlation between perceived indoor air quality and symptoms. The prevalence of symptoms did not explain dissatisfaction with work.