Change in PM10 Concentration by Train Operation in a Single Tunnel Section

Daily operation of urban railways is a major source of large particles affecting PM10 concentration in underground tunnel environments. In this study, temporal variation of PM10 and PM2.5 concentrations were measured using a DustTrak DRX aerosol monitor at the shelter located between adjacent stations on Seoul Metropolitan Railway Line 5. A one-way single tunnel section was chosen to isolate effect of train operation in opposite direction. The monitoring location was about 570 m away from the starting station, where trains traveled at the constant speed. Time-series PM10 and PM2.5 concentrations were categorized by four time periods such as no operation, morning rush-hour, midday, and evening rush-hour periods for both summer and winter. It was found that the train passing caused to increase both PM10 and PM2.5 concentrations shortly. As a result, both PM10 and PM2.5 concentrations were increased steadily during the morning and evening rush-hour periods, on the other hand they remained constantly during the midday period due to the difference in train operation interval.