A noticeable shift in particulate matter levels after platform screen door installation in a Korean subway station

The concentrations of PM10 and PM2.5 were measured continuously in both indoors and outdoors of the Seoul Metropolitan Subway network, Korea from Oct. 2007 to Apr. 2008. As the platform screen door (PSD) system was installed in the end of 2007 (8–16 Dec. 2007), these PM data were analyzed for the evaluation of its effectiveness on the control of PM levels. The results indicated that the mean PM10 concentration in the later period (after PSD installation) was significantly reduced by 16% relative to the earlier period. In contrast, in the case of PM2.5 distinctions were not statistically significant despite a 12% reduction (P < 0.05). The overall results of this study suggest that the installation of the PSD and ventilating system should have served as one of the important components for maintaining the air quality in the model subway system.