O3: Number of days with max. 8-h value above 120 µg/m³, mean value 2021-22-23
 | 0-5 days |
 | 6-10 days |
 | 11-18 days (18 days = target value 2030 Directve) |
 | 19-25 days (25 days = target value current Directive) |
 | >25 days |
Classification of location type
 | rural background |
 | urban background |
 | close to traffic |
 | industrial |