Emission factors for heavy-duty vehicles and validation by tunnel measurements

The paper describes a heavy-duty vehicle (HDV) emission model developed within the framework of three international projects. The model input data were gained from extensive measurement campaigns on HDV engines and HDV and a European data collection program. The paper presents the model and resulting emission factors for HDV. The comparison of the new emission factors with the values given in the actual version of the Handbook Emission Factors 1.2 (Keller et al., Handbuch Emissionsfaktoren für den Straßenverkehr in Österreich (Handbook on Emission Factors for the Street Traffic in Austria), im Auftrag von BMUJF und UBA Österreich, Wien, 1998) shows that emissions of modern HDVs are underestimated clearly by existing emission factor databases. Road tunnel measurements were used to validate the new model.