UNECE Convention on Long-range Transboundary Air Pollution (CLRTAP)

This Convention of the UN Economic Commission for Europe (ENECE) was concluded in Geneva in 1979 and entered into force in 1983. It comprises eight protocols on the reduction of specific air pollutants. Switzerland has ratified all the protocols, and the FOEN is actively involved in a variety of CLRTAP committees.

Within the framework of the Convention on Long-range Transboundary Air Pollution (CLRTAP), the Contracting Parties agree on the following:

  • Recognition of the fact that long-range transboundary air pollution has adverse impacts on the environment, and that human beings and the environment have to be protected against these impacts
  • An obligation to ensure that the Contracting Parties take steps to combat emissions of these air pollutants
  • The creation of a pan-European observation network
  • The creation of committees for the further development and enforcement of the Convention

The Convention therefore forms a framework for political negotiations on combating air pollution for the countries of Europe and Central Asia, as well as for the USA and Canada.


In the meantime, eight protocols have been issued that contain specific obligations for the Contracting Parties. Switzerland has ratified all these protocols, which are as follows:

  • Protocol of 1984 on Long-term Financing of the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP)
  • Protocol on the Reduction of Sulphur Emissions (1985)
  • Protocol concerning the Control of Nitrogen Oxides (1988)
  • Protocol concerning the Control of Emissions of Volatile Organic Compounds (1991)
  • Protocol on Further Reduction of Sulphur Emissions (1994)
  • 1998 Protocols on Heavy Metals and Persistent Organic Pollutants (POPs)
  • 1999 Protocol to abate acidification, eutrophication and ground-level ozone (Gothenburg protocol) concerning the reduction of emissions of sulphur dioxide (SO2), nitrogen oxides (NOx), volatile organic compounds (VOCs), ammonia (NH3), and fine particles (2.5).

Compliance with the CLRTAP

In order to demonstrate compliance with the CLRTAP and its protocols, the Contracting Parties are required to report on a periodical basis to the UNECE secretariat in Geneva which is responsible for the Convention.

Reports are examined and evaluated by an international implementation committee. If requirements are not met, remedial measures are discussed and agreed on.

Working groups and programmes

In addition to its Executive Body, the CLRTAP operates the following main working groups and programmes in which Switzerland is actively involved:

Further information

Last modification 16.07.2021

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