The Decentralised Enforcement of the Provisions on Measurement and Assessment of Air Quality under Directive 2008/50/EC

In the Craeynest case, the Court of Justice interpreted some of the core provisions of the Air Quality Directive 2008/50 in a preliminary ruling. Firstly, the court ruled that national courts may review the siting of sampling points. This manuscript pays special attention to the minimum standard of review that national judges must perform and considers to what extent the Court of Justice departs from its established case law. Secondly, the Court considered that, for an exceedance of a limit value within a zone to exist, it suffices that a pollution level higher than that value is measured at a single sampling point. Thus, the results of all sampling points within a zone must not be averaged. The ruling can be considered as a landmark judgment, as it strengthens the role of citizens, engo’s and national courts in the decentral enforcement of the Air Quality Directive.