Article 2.5.2.2.3.

1.

The location of the sampling points for measuring sulphur dioxide, nitrogen dioxide and nitrogen oxides, particulate matter (PM10 and PM2.5), lead, benzene and carbon monoxide in the air is determined in accordance with the criteria stated in Appendix 2.5.3.3.

2.

In each zone or agglomeration where fixed measurements are the only source of data for assessing the air quality, the number of sampling points for each polluting substance in question may not be less than the minimum number of sampling points stated in Appendix 2.5.3.5, Part A.

3.

In zones and agglomerations where the data from sampling points for fixed measurements are supplemented by data obtained from modelling or indicative measurements, the total number of sampling points stated in Appendix 2.5.3.5, Part A may be reduced by up to 50% if the following conditions have been met:

1 the supplementary methods provide sufficient data to assess the air quality in relation to limit values or alarm thresholds, as well as adequate data for the public;
2 the number of sampling points to be established and the spatial resolution of the other techniques are sufficient to determine the concentration of the polluting substance in question in accordance with the data quality targets stated in Appendix 2.5.3.1, Part A, and allow assessment results that meet the criteria stated in Appendix 2.5.3.1, Part B.

The results of modelling or indicative measurements are taken into account when assessing the air quality for limit values.