The purpose of this study was to investigate the concentration and distribution characteristics of PM₁₀ at high schools classrooms in Ulsan and its surroundings. This study evaluated PM₁₀ levels in classrooms at 79 high schools in Ulsan from May 2008 to May 2009. The average PM₁₀ level was 63.8 μg/m³, and the rate of exceeding the statutory maintenance limit was 16.0%. The average PM₁₀ level was higher in general schools (64.9 μg/m³) compared to professional schools (59.2 μg/m³), and private schools (66.6 μg/m³) was higher than that of public schools (62.5 μg/m³). The average PM₁₀ level (68.4 μg/m³) in general classrooms was significantly (p < 0.01) higher than that in multi-purpose ones (54.6 μg/m³), and first-year student classrooms (73.3 μg/m³) was significantly (p < 0.05) higher than that in second or third grade ones (67.6 μg/m3, 51.5 μg/m³, respectively). The PM₁₀ level in schools in Dong-Gu in the vicinity of assorted industrial complexes was higher than that of schools located in other districts around the Ulsan Metropolitan Area. The regression model showed that PM₁₀ level was positively associated with number of students and relative humidity.

KeywordsPM₁₀, Concentration, High school, Classroom, Ulsan