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Exceedance indicators

These indicators provide no information on the scope or the duration of the excess. The reported number of days depends in fact on the number of monitoring stations, and thus excludes any comparison between periods or regions with a different density of monitoring stations.

1. Number of days with exceedance of the hourly average ozone concentration of 180 µg/m³.
This is the number of days on which the European threshold for informing the public has been exceeded in at least one measuring station in Belgium.

oz_ex180


2. Number of days with exceedance of the hourly average ozone concentration of 240 µg/m³.
This is the number of days on which the European threshold for alarming the public has been exceeded in at least one measuring station in Belgium.

oz_ex240


3. Number of days with exceedance of the daily highest 8-hour mean ozone concentration of 120 µg/m³.
This is the number of days on which the European target value for the protection of human health has been exceeded in at least one measuring stations in Belgium.

oz_ex120