Test Research On Particulate Matter Concentrations Of City Rail Transit System

With the development in the field of transportation, as a rapid safe transportation, rail transit system (RTS) is increasingly accepted by people. With the RTS becomes the main kind of public traffic, indoor air quality in RTS is also becoming an important problem of growing concern. Most rail transit stations located underground, they are basically isolated from the atmosphere except the station entrances and ventilation crossing. Train, building materials, people, etc will emit lager amounts of air pollutants. An increasing number of short-term and long-term epidemiological studies have shown a strong association between particulate matter (PM) concentration and morbidity and mortality due to respiratory and cardiovascular diseases. Many test researches on PM concentrations of city rail transit system have been done in domestic and foreign scholars, but few researches were carried out on comparative analysis between different rail transit systems even different subway environmental control systems.Some representative stations of light rail system and subway system (while the subway system is divided into PSD system and security door system) in Shanghai RTS and Nanjing RTS were selected for survey. Environmental monitoring was carried on respectively in June, July, Augest of2013for summer and December of2013, January, February of2014for winter.The monitoring index include the mass concentrations of PMio and PM2.5.The status of PM concentrations of various environmental control systems were discussed.The similarities and differences between PM concentrations of various environmental control systems were also analyzed.The correlation between mass concentrations of PM10at the platform and inside train, mass concentrations of PM2.5at the platform and inside train, mass concentrations of PM10and PM10-2.5at the platform, mass concentrations of PM10and PM10-2.5inside train were discussed.From this study we can get the following main results:(1) PM concentrations in winter were higher than the corresponding PM concentrations in summer, PM concentrations in subway system were higher than the corresponding PM concentrations in light rail system, PM concentrations at the platform were generally higher than the corresponding PM concentrations inside train, PM concentrations in the security door system were higher than the corresponding PM concentrations in the PSD system;(2) PM concentrations at the platform and inside train in the security door system had both been exceed the standard situation more obvious. The fine particles PM2.5is the main source of pollution of inhalable particles, it means much more attention should be paid to control fine particles;(3) PM concentrations in light rail system were strongly influened by the ambient aerosol concentrations while its influence was very small for the subway system.Regression analysis demonstrated that both the light rail system and subway system, PM10at the platform and PM10inside train were derived from the same source, and between PM2.5at the platform and PM2.5inside train, between PM2.5and PM10-2.5at the platform, between PM2.5and PM10-2.5inside train...