서울시 지하철 시스템 내의 입자상물질(PM 10 , PM 2.5 ) 농도 특성

Seoul subway plays an important part for the public transportation service in Seoul metropolitan area. As the subway system is typically a closed environment, frequent air pollution problems occurred and passengers get malhealth impact. Especially particulate matters (PM) is well known as one of the major pollutants in subway environments. The purpose of this study was to compare the concentrations of PM 10 and PM 2.5 in the Seoul subway system and to provide fundamental data in order to management of subway system. PM 10 and PM 2.5 samples were collected in the M station platform and tunnel of Subway Line 4 in Seoul metropolitan and in an outdoor location close to it from Apr. 21, 2010~Oct. 27, 2013. The samples collected on teflon filters using PM 10 and PM 2.5 mini-volume portable samplers and PM sequential sampler. The PM contributions were 48.6 μg/m³ (outdoor), 84.6 μg/m³ (platform) and 204.8 μg/m³ (tunnel) for PM 10 , and 34.6 μg/m³ (outdoor), 49.7 μg/m³ (platform) and 83.1 μg/m³ (tunnel) for PM 2.5 . The PM 10 levels inside stations and outdoors are poorly correlated, indicating that PM 10 levels in the metro system are mainly influenced by internal sources. In this study, we compared PM concentrations before and after operation of ventilation and Electrostatic Precipitator (EP). Despite the increased PM concentration at outdoor, PM 10 concentration at platform and tunnel showed the 31.2% and 32.3% reduction efficiency after operation the reduction system. The overall results of this study suggest that the installation and operation of the ventilating system and EP should have served as one of the important components for maintaining the air quality in the subway system.