Les cahiers de l'ASN #01 - Nuclear power plants: going beyond 40 years

ASN can suspend the operation of a reactor at any moment in the event of serious and imminent danger. This is part of its duty of permanent oversight of nuclear facilities. A decision such as this is possible during a periodic safety review and at any time during the life of the reactor . Reviews are however an opportunity to reinforce the safety level of the reactors, notably these fourth periodic safety reviews. If EDF were to consider that, for technical or economic reasons, it could not implement ASN’s requirements, the reactor would be shut down. Lastly, final shutdown of a nuclear reactor for energy policy reasons is decided on by the Government and not by ASN . Your questions, ouranswers During this fourth periodic safety review, is it ASN who decides whether or not to shut down a reactor? The licensee transmits the review conclusions report about 6 months after the reactor’s ten-yearly outage inspection . This includes the results of the checks carried out during this ten-yearly outage inspection. This report is examined by ASN and the proposed works are submitted to the public inquiry. ASN then issues a position statement on continued operation up until the next periodic safety review. Pending ASN’s decision and until such time as the work is performed, the reactor can continue to operate . In the same way as after each refuelling outage (or every 12 to 18 months), its restart remains subject to ASN approval. Why does ASN not make its position known regarding the continued operation of a reactor immediately following its ten-yearly outage inspection*? 22 • Les cahiers de l’ASN • September 2018