Subway trains with air cleaners have been newly deployed in the Seoul Metro system. The purpose of this study was to determine differences regarding in-cabin particulate matter with respect to concentrations less than 10 um (PM10) and 2.5 um (PM2.5) through the operation of air cleaners in subway trains. One subway train newly installed with in-cabin air cleaners on Seoul Metro Line number 2 was chosen monitoring in 2020. In-cabin air cleaners were turned-on at both front and back areas while those in the middle area were turned-off while the train was running. In-cabin PM10 and PM2.5 concentrations were measured in each area using a real-time aerosol monitor. Average in-cabin PM10 concentrations were statistically significantly lower (by 15%) in areas with air cleaners turned-on (43.8±12.1 μg/m3) compared to those areas where the air cleaners were turned-off (51.4±15.0 μg/m3). Average incabin PM2.5 concentrations were significantly lower (by 14%) in areas with air cleaners turned on (33.7±12.2 μg/m3) compared to those areas where air cleaners were turned-off (39.2± 14.4 μg/m3). In-cabin PM10 and PM2.5 concentrations ratios were similar regardless of area with air cleaners turned-on or turned-off. The in-cabin PM10 and PM2.5 concentrations were not associated with commute time. Use of air cleaners in subway trains effected reductions in in-cabin PM10 and PM2.5 concentrations.

Abstract
1. 서 론
2. 연구방법
    2.1 연구 대상 및 기간
    2.2 측정 방법 및 데이터 분석
3. 결 과
    3.1 측정구역간 입자상 물질 농도
    3.2 공기청정기 가동 구역에 따른 입자상 물질 농도
    3.3 객차 내 입자상 물질 농도와 관련 요인
4. 고 찰
5. 결 론
References

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• 원수란(국립환경과학원 생활환경연구과) | Soo Ran Won (Indoor Environment & Noise Research Division, National Institute of Environmental Research)
• 이유미(국립환경과학원 생활환경연구과) | Yu mi Lee (Indoor Environment & Noise Research Division, National Institute of Environmental Research)
• 심인근(국립환경과학원 생활환경연구과) | In-Keun Shim (Indoor Environment & Noise Research Division, National Institute of Environmental Research)
• 이종천(국립환경과학원 생활환경연구과) | Jongchun Lee (Indoor Environment & Noise Research Division, National Institute of Environmental Research)
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