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

* See glossary p.24 4th PERIODIC SAFETY REVIEW The hydrotest* Among the key checks in the periodic safety reviews, the hydrotest is a strength test consisting in subjecting the reactor coolant system to a pressure 1.2 times that for which it is designed. Preserving the reactor vessel The reactor vessel cannot be replaced. The challenge is mainly to limit its ageing by modifying the core configuration inside the vessel. The 40-year periodic safety review is a wide-ranging inspection. It is an in-depth examination of the facility, with an appropriate programme of inspections: the aim is to ensure that the works decided on by ASN will be performed in accordance with the intended programme and schedule. These works will be checked in the field by ASN, which will ensure that they are correctly performed in all the facilities concerned. Major issues forsaferNPPs > Conformity issues 10 • Les cahiers de l’ASN