Synthesis of the IRSN report related to the containment of double walled enclosures of the operated fleet

This report presents the IRSN's analysis on studies and modifications planned by EDF within the frame of the VD3-1300 safety re-examination which more particularly concern the third containment barrier of a reactor and of its extensions, as well as the containment of some surrounding buildings. The addressed topics are: the approach associated with the 'containment' safety function, the condition, behaviour and control of the double walled enclosure, the system of suction and filtration of the space between enclosures, the extension of the third containment barrier, the containment of building surrounding the reactor building, the risk of bypass containment, the EDF organisation with respect to the containment safety function