Concentrations of inhalable particles (PM10) have been shown to be exceptionally high in railroad and subway tunnel environments. The elemental composition usually indicates that particles originate in wear from rails, wheels, brake systems and pantographs. To be able to study and abate the contribution to PM10 from different train types, or even individual train sets, detailed traffic data is needed. Most studies are from subways where train types are rather uniform. This study was made in a rail road tunnel, where five different train types traffic the platform. A measurement system for train passages was set up and the data combined with traffic data from the Swedish Transport Administration to pinpoint if certain train types or individual train sets are more important than others for high PM10 concentrations. The results show that an older type of train, with mechanically braking wagons seem to produce most peaks of high PM10 concentrations.
Keywords: railroad, PM10, size distribution, train type.