Spatial distribution of particulate matter (PM 10 and PM 2.5) in Seoul Metropolitan Subway stations

Abstract

The aims of this study are to examine the concentrations of PM 10 and PM 2.5 in areas within the Seoul Metropolitan Subway network and to provide fundamental data in order to protect respiratory health of subway workers and passengers from air pollutants. A total of 22 subway stations located on lines 1–4 were selected based on subway official's guidance. At these stations both subway worker areas (station offices, rest areas, ticket offices and driver compartments) and passengers areas (station precincts, subway carriages and platforms) were the sites used for measuring the levels of PM. The mean concentrations of PM 10 and PM 2.5 were relatively higher on platforms, inside subway carriages and in driver compartments than in the other areas monitored. The levels of PM 10 and PM 2.5 for station precincts and platforms exceeded the 24-h acceptable threshold limits of 150 μg/m 3 for PM 10 and 35 μg/m 3 for PM 2.5, which are regulated by the U.S. Environmental Protection Agency (EPA). However, levels measured in station and ticket offices fell below the respective threshold. The mean PM 10 and PM 2.5 concentrations on platforms located underground were significantly higher than those at ground level ( p < 0.05).