Access to justice within the EU in cases relating to air quality
Therefore, an individual person (and also an NGO) has a right to see the action plan elaborated, since the key element in the AQD is the setting of binding limit values together with the obligation to adopt air quality plans containing adequate measures to achieve compliance in the shortest time possible. The CJEU held that the plans intended to eliminate the threat to human health as quickly as possible and that the elaboration of a plan was the consequence foreseen by the EU legislation for the cases that the alert thresholds were at risk of being exceeded 
. In the cases under Article 23 AQD, the limit values are not only at risk of being exceeded, but are actually exceeded which makes the threat to human health even greater. The ability to rely on these obligations have allowed people to take authorities to court and hold them accountable for their failures to protect the right to clean air.
The Court of Justice limited the right of persons to request a specific content of a plan . It held that the public authorities were to take measures to keep the time of (the risk of) exceedance as short as possible, but that they benefitted of a large amount of discretion, so that specific measures could not be asked for.
As regards German law, the Bundesverwaltungsgericht clarified that a progressive reduction of the air pollution was not necessarily in compliance with EU law; it could be controlled by the courts, whether such a reduction was really reached as quickly as possible . Also the United Kingdom Supreme Court decided that the question, whether an air quality plan (under Article 23 of the air pollution directive) brought down the air pollution as quickly as possible, was subject to judicial control . While it has thus no rights, a person may point out before a court, to measures which would more quickly bring the air pollution back to the required values. In Case C-404/13 ClientEarth, the CJEU confirmed that the national court should order any measure necessary to bring the air pollution plan into line with EU air quality legislation.
Furthermore, the individuals must be able to challenge the air pollution monitoring system in their cities (Case C-723/17 Craeynest and Others) because the AQD lays down detailed rules concerning the use and location of sampling points to measure air quality in zones and agglomerations comprising the territory of each Member State. According to the Court, some of those rules impose a clear, precise and unconditional obligation, which means that they can be invoked by individuals against the State. This is the case, in particular, with regard to the obligation to establish sampling points in such a way that they provide information on the most polluted locations, and the obligation to establish at least a minimum number of sampling points. It is for the national courts to verify whether those obligations have been complied with. In this respect, the average values across a whole zone or city are insufficient as they may underestimate the actual exposure to polluted air.
Similar approach applies to the obligations in the NEC Directive. The natural and legal persons directly concerned must be able to require the competent authorities, if necessary by bringing the matter before the national courts, to observe and implement such rules of EU law.
There is certain discretion of Member states in adopting programmes and limits to that discretion prescribed by Article 6 NEC Directive. The Directive nevertheless involves limits on its exercise, which are capable of being relied upon before the national courts, relating to the appropriateness of the body of policies and measures adopted or envisaged within the framework of the respective national programmes to the objective of limiting emissions of the pollutants covered to amounts not exceeding the ceilings laid down for each Member State.