5. This Part sets out the minimum number of sampling points for fixed measurement of Group B pollutants to assess compliance with target values in zones where fixed measurement is the sole source of information.
| Population of zone (thousands) | Where maximum concentrations exceed the upper assessment threshold(1) | Where maximum concentrations are between the upper and lower assessment thresholds | ||
|---|---|---|---|---|
| Arsenic, Cadmium, Nickel | Benzo(a)pyrene | Arsenic, Cadmium, Nickel | Benzo(a)pyrene | |
(1) To include at least one urban-background station and for benzo(a)pyrene also one traffic-oriented station provided this does not increase the number of sampling points. | ||||
| 0–749 | 1 | 1 | 1 | 1 |
| 750–1999 | 2 | 2 | 1 | 1 |
| 2000–3749 | 2 | 3 | 1 | 1 |
| 3750–4749 | 3 | 4 | 2 | 2 |
| 4750–5999 | 4 | 5 | 2 | 2 |
| 6000 or more | 5 | 5 | 2 | 2 |
6. For the assessment of pollution in the vicinity of point sources, the number of sampling points for fixed measurement shall be determined taking into account emission densities, the likely distribution patterns of ambient air pollution and potential exposure of the population. The sampling points shall be sited such that the application of the measures referred to in regulation 7(2) can be monitored.