This research investigated the characteristics of PM10 and PM2.5 concentrations at the main subway stations in Busan. Annual mean PM10 concentrations at the Seomyeon 1- waiting room and platform were 51.3 ㎍/㎥ and 47.5 ㎍/㎥ , respectively, and the annual PM2.5 concentration at the Seomyeon 1- platform was 28.8 ㎍/㎥ . PM2.5/PM10 ratio at Seomyeon 1-platform and Dongnae station were 0.58 and 0.53, respectively. Diurnal variation of PM10 concentration at subway stations in Busan was categorized into four types, depending on the number of peaks and the times at which the peaks occurred. Unlike the areas outside of the subway stations which reported maximum PM10 concentration mostly in spring across the entire locations, the interiors of the subway stations reported the maximum PM10 concentration in spring, winter, and even summer, depending on their location. PM10 concentration was highest on Saturday and lowest on Sunday. The numbers of days when PM10 concentration exceeded 100 ㎍/㎥ and 80 ㎍/㎥ per day over the last three years at the subway stations in Busan were 36 and 239, respectively. The findings of this research are expected to enhace the understanding of the fine particle characteristics at subway stations in Busan and be useful for developing a strategy for controlling urban indoor air quality.

Abstract
 1. 서 론
 2. 재료 및 방법
 3. 결과 및 고찰
 4. 요약 및 결론
 REFERENCES

• 전병일(신라대학교 에너지화학공학부) | Byung-Il Jeon (Department of Environmental Engineering, Silla University) Corresponding author