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Non-exhaust road traffic induced particle emissions - Evaluating the effect of mitigation measures on air quality and exposure.

Traffic non-exhaust particle emissions are the main reason for high PM10 levels and have been responsible for the exceedances of the EU air quality limit values along densely trafficked roads in many Nordic cities. While exhaust emissions will substantially decrease in the coming years due to more stringent regulation, the non-exhaust emissions are expected to stay at the same level or increase with traffic volume and will represent a dominating part of the total PM emissions.

Models are essential to understand the emission dynamics of non-exhaust particles in multiple urban environments but they still rely on very little data to support the parameterizations. Models are potentially a very important tool to study and quantify the effect of abatement measures in urban environments. However, for further improvements of models more extensive high-quality data from both field and laboratory studies is still required.

In a previous Nordic collaborative project, NORTRIP (Johansson et al. 2012; Denby et al., 2013), an emission model for non-exhaust particles was developed based on knowledge from excessive field and laboratory studies in the Nordic countries on how road properties, road operation, traffic and meteorology interact in production and emission of non-exhaust particles. The NORTRIP project developed a process based non-exhaust emission model that was applied in 7 street locations in the Nordic capital cities.

The NOTRTIP model is currently the most comprehensive process based non-exhaust model available. The NORTRIP model is able to serve as a platform to study the different possibilities to control the emissions, which is the aim of NORTRIP-2 project.


Liisa Pirjola
Project Director
tel. +358 9 7424 6117
liisa.pirjola [at]