Which concentrations may not be exceeded?
The 2008 European directive on air quality sets limit values for some pollutants. They are science-based concentration levels that must not be exceeded in order to reduce harmful effects on human health and/or the environment as a whole.
The limit values are maximum concentrations expressed in µg/m³ for different time periods: hourly, daily or annual average concentration. There are levels for sulphur dioxide, nitrogen dioxide, PM₁₀, PM₂.₅, lead, benzene and carbon monoxide.
|
Pollutant |
Averaging period |
Limit value |
Date by which limit value is to be met |
|
PM₁₀ |
Annual average |
40 µg/m³ |
Since 1 January 2005 |
|
|
Daily average |
50 µg/m³ |
Since 1 January 2005 |
|
PM₂.₅ |
Annual average |
25 µg/m³ |
Since 1 January 2015 |
|
Benzeen |
Annual average |
5 µg/m³ |
Since 1 January 2010 |
|
CO |
Maximum daily eight hour mean |
10 µg/m³ |
Since 1 January 2005 |
|
Lood |
Annual average |
0,5 µg/m³ |
Since 1 January 2005 |
|
NO₂ |
Annual average |
40 µg/m³ |
Since 1 January 2010 |
|
|
Hourly average |
200 µg/m³ |
Since 1 January 2010 |
|
SO₂ |
Daily average |
125 µg/m³ |
Since 1 January 2005 |
| Hourly average | 350 µg/m³ |
Since 1 January 2005 |
In addition to these limit values, which are mandatory to attain, the directive also describes target values, information thresholds and alert thresholds for various pollutants. Target values are concentrations to be attained where possible, while information and alert thresholds are concentration levels at which Belgium is obliged to inform the public.
Every year, we test the entire Belgian territory against these limit values in our annual air quality report.
