Target values
Article 3
1. Member States shall take all necessary measures not entailing disproportionate costs to ensure that, as from 31 December 2012, concentrations of arsenic, cadmium, nickel and benzo(a)pyrene, used as a marker for the carcinogenic risk of polycyclic aromatic hydrocarbons, in ambient air, as assessed in accordance with Article 4, do not exceed the target values laid down in Annex I. 2. Member States shall draw up a list of zones and agglomerations in which the levels of arsenic, cadmium, nickel, and benzo(a)pyrene are below the respective target values. Member States shall maintain the levels of these pollutants in these zones and agglomerations below the respective target values and shall endeavour to preserve the best ambient air quality, compatible with sustainable development. 3. Member States shall draw up a list of the zones and agglomerations where the target values laid down in Annex I are exceeded. For such zones and agglomerations, Member States shall specify the areas of exceedance and the sources contributing thereto. In the areas concerned, Member States shall demonstrate the application of all necessary measures not entailing disproportionate costs, directed in particular at the predominant emission sources, in order to attain the target values. In the case of industrial installations covered by Directive 96/61/EC this means the application of BAT as defined by Article 2(11) of that Directive.