Navigation path

News feeds

Nuclear energy

Stress tests

Stress tests globally

All nuclear power plants in the EU underwent stress tests and peer reviews in 2011 and 2012. Many other countries and territories also conducted comprehensive nuclear risk and safety assessments, based on the EU stress-test model. These include Switzerland and Ukraine (both of which fully participated in the EU stress tests), Armenia, Turkey, Russia, Taiwan, Japan, South Korea, South Africa and Brazil.

The European Commission is now holding discussions with some of these countries, e.g. Armenia and Turkey, regarding possible peer review of their stress tests.

Taiwanese nuclear stress tests

7 November 2013. The EU peer review concludes that the safety standards applied in Taiwanese nuclear power plants are generally high and comply with international state-of-the-art practices. Neither the Taiwanese nuclear operator nor the regulator found any safety shortcomings which would require the immediate shutdown of any power plants.

However, the EU peer review strongly recommends further improvements in view of Taiwan's vulnerability to natural hazards such as earthquakes, flooding, tsunamis and volcanos.

The peer review – performed by the European Commission and the European Nuclear Safety Regulators' Group (ENSREG) – calls for action to make the power plants more robust against the effects of large earthquakes and flooding, e.g. by building higher tsunami protection walls. Also, more up-to-date methods and data should be used to evaluate seismic and flooding risks.

Taiwan has been generating power from nuclear plants since 1977. There are currently three plants in operation and one under construction. All have undergone the stress tests and consequently the EU peer review.

Stress tests and Peer Review Process

On 26 April 2012 the European Commission welcomed the adoption of the ENSREG stress test report and the agreement to examine some safety aspects in more detail and prepare a follow up in the next few months:

The European Commission adopted on 24 November 2011 a Communication looking at the first findings of the stress tests.


Following the nuclear accident in Fukushima, the European Commission and the European Nuclear Safety Regulators' Group (ENSREG) agreed on 25 May 2011 on voluntary tests for the EU's 143 nuclear power reactors. These tests were based on a common methodology and assess both natural and man-made hazards (i.e. effects of airplane crashes and terrorist attacks). The assessments were conducted by independent national authorities and through peer review. The tests started on 1 June 2011.

On 23 June 20111 the Commission and a number of third countries agreed on a joint declaration:

WENRA proposal - "Stress tests" specifications

The Fukushima accident triggered an immediate and coordinated response from the EU, aiming to identify potential further safety improvements for nuclear plants.

On 25 March 2011, the Heads of States or Governments of the EU Member States concluded that the safety of all EU nuclear plants should be reviewed, on the basis of comprehensive and transparent risk and safety assessments ('stress tests'). They invited the Commission and ENSREG to develop the scope and modalities of these tests, fully involving Member States and the available expertise, notably the Western European Nuclear Regulators Association (WENRA).

WENRA is a network of Chief Regulators of 16 EU Member States and Switzerland, as well as of other interested European countries which have been granted observer status. During their plenary meeting in March 2011, WENRA developed a technical definition of the 'stress tests', as well as an initial approach on how they should be applied to nuclear facilities across Europe in terms of methodology and timeframe.


Communication on results of the stress tests

On 4 October 2012, the European Commission released the Communication on the results of the stress tests. This document highlights that European nuclear power plants have generally high safety standards but further improvements are needed in almost all of them.