Ecology & Safety, Volume 13, 2019

Abstract: By being part of the public buildings with the highest usability ratio, educational establishments are bound by certain requirements on the construction, maintenance, control and especially the reduction of the risk factors associated with school environment and related to adolescents’ health and physical development. Air quality in school buildings and its role as a multicomponent risk factor, having a modulating effect on the health of students and teachers, has been the subject of an epidemiological study carried out in three comprehensive schools in the town of Haskovo. The study aimed at identifying the main air pollutants in the classrooms. Some physical, chemical and biological indicator parameters, such as air temperature, relative humidity, PM10, PM2.5, ozone, carbon monoxide, carbon dioxide, formaldehyde, nitrogen dioxide, volatile organic compounds, moisture and mold presence, have been analyzed. It was found that a large percentage of the schoolchildren in the early school age (grades 1-4) occupied classrooms where carbon dioxide (90% of the classrooms) and fine particulate matter (50% of the classrooms) significantly exceeded the recommended concentrations for each. The remaining pollutants marked deviations from their respective standards only in isolated cases. The dynamics of the abovementioned pollutant levels measured in real time during classroom occupation as well as the air quality in the classrooms, defined by the microclimatic parameters and the presence of some chemical pollutants, were directly related to ventilation intensity, classroom occupancy, student activity, heating fuel type and building location. The results of this study generally support the hypothesis of a relationship between air quality in classrooms, their occupancy and ventilation intensity.