Schedule 6 Critical levels for the protection of vegetation
Oxides of Nitrogen
| Averaging period | Critical level |
|---|---|
| Calendar year | 30 µg/m3 NOx |
Sulphur dioxide
| Averaging period | Critical level |
|---|---|
| Calendar year and winter (1st October to 31st March) | 20 µg/m3 |
Oxides of Nitrogen
| Averaging period | Critical level |
|---|---|
| Calendar year | 30 µg/m3 NOx |
Sulphur dioxide
| Averaging period | Critical level |
|---|---|
| Calendar year and winter (1st October to 31st March) | 20 µg/m3 |