AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Source Apportionment of Particles in London Paddington Station
UVEN CHONG, Jacob Swanson, Adam M Boies, University of Cambridge
Abstract Number: 524 Working Group: Source Apportionment
Abstract Enclosed transit stations with diesel-powered trains are a health risk because of the close proximity of particle emissions to passengers and workers. Diesel train emissions are regulated directly by EU emissions standards and indirectly by the sulphur content of gas oil. To evaluate the impact of diesel engine exhaust within a train station relative to other emission sources, particulate matter (PM) measurements were taken at London Paddington Station. The purpose of this study is to measure the air quality (particle number and mass) within Paddington and determine the sources of particle emissions. We determine the relative contribution of PM from various sources by measuring particles in different locations and analyzing their chemical and size characteristics.
An initial station survey was conducted using a P-TRAK 8525 and OPS 3330 (TSI, Inc.) to measure the airborne particle number concentration below 0.1 micro-meters and between 0.3-10 micro-meters, respectively. Elevated levels of PM were observed during departing and arriving train activity, with departing engine acceleration causing higher levels of PM than braking from arriving trains. Measurements near food vendors also showed elevated levels of particles, indicating that cooking may be a large contributor to airborne particulates within the station.
A subsequent measurement campaign was conducted to apportion the sources of PM. PM mass concentration measurements were taken continuously at 6 locations using a TSI AM510 monitor and a portable ELF Pump with a filter. A CPC and a DMS50 (Cambustion, Inc.) were rotated between three locations. Measurements were taken with and without a catalytic stripper to determine the EC/OC ratios. Filtered PM samples were used to determine the chemical composition of particles. The results of these measurements demonstrate the relative contribution of engine and cooking particle production and provide information for policy decisions to improve air quality in Paddington by targeting the appropriate sources.