Ozone Act
The Ozone Act regulates the measurement of ozone concentrations in the air, provides for the corresponding public information, and obliges the Federal Government to implement measures to reduce emissions of ozone precursor substances and to ensure compliance with target values.
The currently valid version of the Ozone Act dates back to 2003, when it was amended to implement the new EU Directive 2002/3/EC (EUR-Lex) on the ozone content of ambient air. This amendment introduced target values and long-term objectives for the protection of human health and vegetation, as well as measures to ensure their compliance. At the same time, the alert thresholds for informing the public were adjusted to align with the EU regulations. Since 2008, the ozone content of the air has been regulated under Directive 2008/50/EC, which incorporated the provisions of Directive 2002/3/EC unchanged.
The Ozone Act has remained a separate law because ozone differs significantly from the pollutants regulated under the Air Pollution Control Act (Immissionsschutzgesetz-Luft), due to its formation in the atmosphere as a secondary pollutant and the predominance of long-range transport over local formation.
The first section of the Ozone Act contains provisions on the operation of monitoring stations, data exchange between the federal states and the Federal Environment Agency, periodic reporting on ozone concentrations, and informing and warning the public when the relevant thresholds are exceeded.
The second section sets out the target values and long-term objectives for ozone concentrations in the air, reduction targets for ozone precursor substances, and a reporting obligation to the National Council. It also establishes a duty for the Federal Government to implement measures to ensure compliance with the target values, as well as an obligation for the provincial governors to take any necessary immediate measures.
| Information threshold | 180 micrograms per cubic metre (µg/m³) | one-hour mean (H1) |
| Alert threshold | 240 µg/m³ | one-hour mean (H1) |
| Health protection | 120 µg/m³ | highest eight-hour mean (H8) of the day, may be exceeded on average over 3 years on no more than 25 days per calendar year |
| Protection of vegetation | 18,000 µg/m³·h | AOT40, May to July, averaged over 5 years (Note on AOT40: sum of the amounts by which all one-hour means between 08:00 and 20:00 CET exceed 80 µg/m³) |
| Health protection | 120 µg/m³ | highest eight-hour mean (H8) of the calendar year |
| Protection of vegetation | 6,000 µg/m³·h | AOT40, May to July (Note on AOT40: sum of the amounts by which all one-hour means between 08:00 and 20:00 CET exceed 80 µg/m³) |
According to Section 12 of the Ozone Act, the Federal Minister for the Environment must submit a written report to the National Council every three years on the status, development, and forecast of ozone concentrations and emissions of ozone precursor substances, as well as on measures to reduce emissions and their effectiveness. These reports can be accessed on the Parliament’s website.
On the basis of the Ozone Act, two regulations have been enacted: the “Regulation on the Classification of the Federal Territory into Ozone Monitoring Areas” defines areas in which largely uniform ozone levels and trends occur and on the basis of which public information is provided (see map). The “Regulation on the Measurement Concept and Reporting under the Ozone Act” sets out details regarding measurement, data publication, and public warnings.