Report 680705009/2008 J. Wesseling | F. Sauter Non-linearity in the NOx/NO2 conversion RIVM Report 680705009/2008 Non-linearity in the NOx/NO2 conversion J. Wesseling, RIVM F. Sauter, RIVM Contact: Joost Wesseling RIVM/LVM
[email protected] This investigation has been performed by order and for the account of Ministry of VROM, within the framework of the project Urban Air Quality, project M/680705/07. RIVM, P.O. Box 1, 3720 BA Bilthoven, the Netherlands Tel +31 30 274 91 11 www.rivm.nl RIVM National Institute for Public Health and the Environment P.O. Box 1 3720 BA Bilthoven The Netherlands www.rivm.com © RIVM 2008 Parts of this publication may be reproduced, provided acknowledgement is given to the 'National Institute for Public Health and the Environment', along with the title and year of publication. 2 RIVM Report 680705009 Abstract Non-linearity in the NOx/NO2 conversion The yearly average NO2 concentration along roads is influenced by the way it is calculated. The RIVM has analyzed the mathematical relations involved of some of the models being used in the Netherlands. With this information, the differences between model calculations as well as between models and experimental data can be understood in a better way. On locations with a lot of traffic the yearly average limit value for NO2 is exceeded regularly. In the Netherlands compliance with EU air quality regulations is usually checked using the results of model calculations. The models being used in the Netherlands calculate the NO2 concentrations in several ways. It is long known that different calculation schemes produce different results.