Criteria for assessing the spatial representativeness areas of sampling points
Article 5
1. Member States shall assess the spatial representativeness area of sampling points in accordance with the provisions laid down in this Article. 2. Member States shall identify locations or areas with similar concentrations to those at a sampling point for a given pollutant using tolerance levels in accordance with Article 6(3) for measurements and tolerance levels in accordance with Article 7(2) for modelling applications. For the purpose of the first subparagraph, the central value shall be selected as follows: (a) where measurements are used, the annual mean of the concentration measured at the sampling point is used as the central value to identify locations with similar concentrations; (b) where modelling applications are used, the annual mean of the concentration modelled for the sampling point location is used as the central value to identify areas with similar concentrations. Member States may use other metrics than the annual mean, such as relevant percentiles or seasonal averages, including hourly, eight-hour, daily, AOT40, and winter averages for pollutants with limit or target values established for metrics other than the annual mean. 3. Member States shall refine the areas identified pursuant to paragraph 2 in accordance with the rules laid down in this paragraph. The geographical area may include non-contiguous domains but shall, in principle, be limited in its extension by the borders of the zone under consideration. For sampling points intended to be representative of areas broader than a given air quality zone, Member States may apply alternative geographical limitations. Locations at or near heavily trafficked roads in suburban or rural areas may be excluded from the areas identified for urban background sampling points even if concentrations in those areas fall within the tolerance interval calculated for the sampling point. If the area identified for a sampling point covers a wider area than the city or urban area in which the sampling point is located, the area identified may further be limited to the city or the urban area. Locations where air quality assessment is not required pursuant to point A.2 of Annex IV to Directive (EU) 2024/2881 may be excluded from the identified area. 4. Member States shall consider source-related information to exclude locations from the areas identified and refined in accordance with paragraphs 2 and 3 that have significantly different pollution profiles or dispersion conditions. Member States shall exercise expert analysis to identify such locations.