Emissions of particulate matter from railways – onboard and tunnel measurements

There are increasing concerns about health risks associated with high levels of particulate matter in air. A major source of these particles is combustion engines but also particles originating from wear of material can be important. It is in this context of interest to study particle emissions from railways. A number of studies have reported high concentrations of particles in underground stations and subways. There are few studies reporting levels of particles in railway environments above ground and no studies reporting emission factors or the variability in emissions with driving pattern.In the report a number of measurements of particle emissions from railway are presented. In the first part of the report, results from tunnel measurements where abrasion particles from different types of trains are measured in two campaigns are reported. Further, emission factors are calculated from these measurements. In the second part of the project, measurements were done with instruments positioned under a train. This provided information on how the particle emissions vary with driving patterns