EXPOSURE LEVEL OF PARTICLE MATTER MATERIALS AND CO2 IN SUBWAY CARRIAGES IN SEOUL

The objective of this study is to provide research results of the actual conditions concerning the concentrations of PM10, PM2.5, PM1 and CO2 among particle and gaseous pollutants in a subway carriage. Mean concentrations of PM10, PM2.5 and PM1, and CO2 in a subway carriage were investigated as 215.1±101.4 ㎍ m-3, 86.9±38.6 ㎍ m-3, 27.0±11.4 ㎍ m-3, and 1,588±714 ppm, respectively. These mean concentrations in a subway carriage were higher when it ran on an underground track than on a ground track. For different hours, particle matter materials ' concentrations were the highest in the morning, followed by noon and evening, and for the CO2 concentration was high in order of morning, evening and noon. In the result of the correlation test among pollutants, the correlation degree between PM10 and PM2.5 was 0.92, and that between PM2.5 and PM1 was 0.94. It showed high positive correlation and the inclusion rate of PM2.5 to PM10 was 41±7 % and that of PM1 to PM2.5 was 32±4%. And in the relation of the number of people in a subway carriage to PM10 and CO2, whereas the concentration of PM10 had negative relation to the number of people, that of CO2 had positive relation to it. With these pollutants, to calculate the result of adequate numbers of passengers in a passenger carriage by using a regression equation showed 61 persons (34.06 + 0.04 CO2 (ppm)-0.09 PM10( ㎍ m-3) (R2=0.30, p<0.01, n=707), are needed to maintain each pollutant below the level to the criteria value, applicable to a station building