A Study of Particulate Matter (PM2.5) Concentration Variance by Distance from Train Platform at a Major Bay Area Rapid Transit (BART) Railway Station

Over the past five years, the East Bay Academy for Young Scientists (EBAYS) has been investigating air quality at Bay Area Rapid Transit (BART) train stations. In particular, prior EBAYS research has revealed extremely high levels of particulate matter (PM 2.5) at the multi-leveled Embarcadero Station, which is underground and is one of the most frequently visited stations in the entire BART system. During the summer of 2017 data was collected to determine whether or not air quality differed on the three levels of this station. In conducting this study the research team was separated into pairs, each pair in possession of a Dustrak II or AirBeam PM analyzer and each pair assigned to a particular level. Within each measurement trial data was collected for 15 minutes. Measurements were also made on the eastern and western ends of the platforms to detect possible variations in PM concentration. Preliminary results obtained thus far indicate that dangerously high levels of PM 2.5 concentration occur on all three levels of the station. This is especially problematic because it suggests that individuals who spend extensive amounts of time at this station (e.g., station agents and other workers) are exposed to extremely high PM 2.5 concentration levels and as a result are working under conditions that are quite hazardous to their health. Based on observations made during testing, increased levels of PM 2.5 tend to correlate with the departure or arrival of BART trains that results in particulate matter being scattered about the train platform and other levels. Further studies should be conducted to verify this observation and to contribute to better understanding the sources and behavior of PM 2.5 at each level of the station.