During the Limitation of Oxidant Prodn. (LOOP) campaign, different instruments were deployed, providing a complete data set. This will be used to evaluate the model and its ability to reproduce pollution events. Then, the complete data set will be used for a better definition of the model inputs. The final aim of the LOOP project is to use the model to test different abatement strategies, particularly by defining the region where ozone prodn. is NOx or VOC sensitive.