This report presents an assessment of the operational characteristics of the filtration function used during the recirculation phase of safety injection system (SI) and containment spray system (SS) in the event of a break of the primary system in the containment for the French pressurized reactors (58 reactors), which have been designed according with the Regulatory Guide 1.82 (revision 1) published in 1985.
In spite of the lessons learned from the BARSEBACK accident occurred in 1992 and the corresponding questioning about the appropriate character of the requirements of this Regulatory Guide, Electricité de France has always proclaimed the compliance of the French plants with revision 1 of the Regulatory Guide 1.82 and has refused to review this position.
Consequently, the "Institut de Radioprotection et de Sûreté Nucléaire" has decided to perform its own assessment. A general overview of the literature has been conducted between October 1999 and November 2000, questioning the capability of the safeguards systems to operate during recirculation phase which resulted in defining an approach methodology and writing technical specifications related to the French design reactors.
After this general overview, the "Institut de Radioprotection et de Sûreté Nucléaire" has decided to perform a detailed study on the risk of sump plugging for the French reactors.