Convention on Nuclear Safety ensures high global safety standards in nuclear power plants

The Convention on Nuclear Safety (CNS) is an international agreement aimed at increasing the safety of civil-sector nuclear power plants throughout the world. Switzerland is one of the founder nations of the CNS and is actively involved in strengthening the accord.

The Convention on Nuclear Safety (CNS) was the first legal instrument regarding the safety of nuclear power plants to be introduced at international level. At the conclusion of the Vienna diplomatic conference of the International Atomic Energy Agency (IAEA) in June 1994, the then IAEA Director Hans Blix stated: “The promotion of safety in nuclear installations is an important national and international objective. This Convention will give many well-known principles the force of law. It will also establish innovative mechanisms to help us ensure that the letters of this law translate into safe nuclear reality.”

The international Convention on Nuclear Safety has its origins in a resolution adopted by the IAEA General Conference in 1993 . Events at Chernobyl in 1986 had triggered calls for internationally binding safety standards. The Convention was finally signed on 17 June 1994, and it came into force on 24 October 1996. By mid-2013, 76 countries had signed the Convention as contracting parties. Ten countries are still in the process of ratifying their decisions to become contracting parties to the Convention.


Switzerland is one of the founder nations

Switzerland signed the Convention on 31 October 1995; it was ratified on 12 September 1996, and was brought into effect on 11 December 1996. Switzerland is therefore numbered among the founder nations of the accord. Ever since the first CNS meeting was held in 1999, this country has taken part in the Review Meetings that are held every three years in Vienna.

In the context of the CNS, Switzerland advocates the strengthening of international safety requirements and aims to make the obligations more binding. When reviewing the safety of nuclear power plants, countries which are contracting parties to the Convention should in future apply site-specific hazard assumptions in keeping with the latest advances in science and technology. They should also have the design and operation of their nuclear power plants and the work of their supervisory authorities reviewed by international experts at regular intervals. Countries should be obliged to publish their National Reports, review results and decisions.


Regular reporting

In order to achieve the stated objectives, the contracting parties or member countries are currently obliged to apply the principles of the 35 articles of the Convention, they must submit a National Report on the implementation status of requirements arising from the Convention every three years, and they must take part in the International Review Meetings in Vienna. The National Report on the current safety status must always be submitted to the CNS Secretariat at the IAEA about six months prior to these conferences.

The National Reports must provide information about the specified subjects:

  • Nuclear plants currently in operation
  • Legislation and official regulatory framework
  • National supervisory authority
  • Responsibility of the licensee or operator
  • Priority accorded to safety
  • Financial and human resources
  • Human factors
  • Quality assurance
  • Safety assessment
  • Radiation protection
  • Emergency preparedness
  • Choice of location, design, construction and operation of nuclear plants


Next meeting in 2014

The sixth regular meeting is planned for spring 2014. Switzerland will submit its National Report for this meeting to the IAEA next week.