Several factors can explain the high levels of particle concentrations in underground transportation systems. One of the main particle sources is trainís mechanical braking system. The mechanical braking is decreasing with the renewal of rolling stock, new trains have other brake kind: the electrodynamic braking. This technology decreases the mechanical braking use and this one is more and more efficient on new trains. Two stages have been planned to study the brake technology (with electrodynamic braking //without electrodynamic braking) on particulate air pollution. PM2.5 mass concentration and PM10 mass concentration were simultaneously measured at Colonel Fabien subway platform. The chemical composition of the fine particle fraction (PM2.5) and the coarse fraction (PM10-2.5) is measured using PIXE analysis. In this campaign, the brake technology has an impact on the air quality. The electrodynamic braking use lowers the PM10 mass concentration by a factor of 4.3. Moreover, the trainís mechanical braking system is responsible for a higher iron mass percentage in the coarse particle fraction.
Keywords: subway, air quality, train, indoor