Ambient air soot concentrations in Munich public transportation systems

Airborne soot concentrations in fine dust up to 10 μm mean particle diameter were measured in seven buses and tramways during regular rides in 4 h periods at different daytimes in Munich. With regard to the traffic-related measurements, the main part of particle emissions is caused by motor vehicles. Between March 1995 and July 1996, a total of 105 analyses were accomplished and total as well as elemental carbon were measured. The average value of all measurements amounted to 32.1 μg total carbon/m3 and 14.8 μg C/m3 for elemental carbon. In the mean, 45.2% of the total carbon belonged to the elemental carbon.