Use of safety probabilistic assessments in the framework of the decennial safety overhaul

Every 10 years operating nuclear reactors are submitted to an assessment of their safety level. Initial probabilistic safety assessment (PSA) are upgraded to take into account the feedback experience of the reactor and the new technological advances in terms of safety. For any proposed modification of the plant, the safety benefit is assessed through the upgraded PSA. The knowledge of the safety benefit and its cost for each modification enables the plant manager to define priorities. (A.C.)