Assessment of the in- /outdoor air quality through diffusive sampling and mobile measurements in a school edification - Stuttgart

It is widely known that one of the pressing environmental problems of major conurbations is the adverse effects of air pollution. With the aim of assessing the in-/outdoor air quality in a German elementary school in Stuttgart; diffusive sampling of NO_x and NO₂ along with mobile measurements of O₃, NO_x, particulate matter, and black carbon were conducted. For the diffusive sampling, 4 sets of triethanolamine absorption-based surfaces located in 23 different strategic points in the school were implemented over a total 7-week time period. The obtained NO_x average values oscillate between 20 to 44 μg/m³, and 8 to 23 μg/m³ for NO₂. Eight daily mobile measurements were conducted over a 2-week time period covering all classrooms and halls from the school. Average values between 7 and 17 ppb for NO₂, between 8 and 20 ppb for NO and between 14 to 50 ppb for O₃ were observed. For Particulate Matter, average values were obtained between 2 to 85 μg/m³ and 1 to 17 μg/m³ for PM10 and PM2.5 respectively. Soot average concentrations were found between 100 and 1,700 ng/m³. In general, peak values are present in forced-ventilated rooms close to the main road and it is noticeable that the pollution levels in and outside the school are not high enough to be considered harmful for the children’s health.