1186685 - Characteristic of Particulate Matter Levels in Classrooms of Elementary Schools in South Korea by Indoor and Outdoor Influencing Factors (Student Poster #25)

Students spend a lot of time for a school and are more exposed to indoor air pollution. Therefore, indoor air quality of schools is a very important factor influencing student health. In this study, in order to assess the effect of outdoor particulate matter on indoor particulate matter, statistical analysis was conducted by measurement data of indoor and outdoor PM (PM10 ( < 10 um aerodynamic diameter) and PM2.5 ( < 2.5 um aerodynamic diameter)) from twenty elementary schools in South Korea. The correlation analysis between the indoor and outdoor PM was identified according to the three surrounding environments (traffic area, agricultural area, commercial area). In addition, the ratio of indoor/outdoor PM (I/O ratio) was performed to estimate the emission source of indoor PM concentration. As a results, the correlation analysis was confirmed that the correlation between PM10 was lower than PM2.5 in every surrounding environment. In addition, the concentration of PM10 and PM2.5 in the traffic area were higher than those in agricultural, commercial area. The I/O ratio of PM10 was similar to 1 (1 >: 55%; 19 classrooms, 1<: 45%; 16 classrooms). This means that there is no difference in PM10 levels indoors and outdoors. On the other hand, the I/O ratios of PM2.5 were smaller than 1 (1>: 83%; 29 classrooms, 1<: 17%; 6 classrooms). This suggests that concentrations of outdoor PM2.5 are higher than those of indoor PM2.5. Thus, a coarse particle (PM2.5-10) in classrooms is mainly formed by internal sources, whereas PM2.5 are caused by external sources.