French regulatory requirements concerning severe accidents in PWRs and associated research programme

Safety objectives in regard to populations are discussed and pressurized water reactor safety goals are outlined. For design purposes the design objective outlined logically aims at the largescale non-degradation of the core. A description is given of ultimate procedures involving the proceeding of physical phenomena induced by severe accidents. Thermohydraulics in double phase transient is discussed. The approach to safety doctrine in France in regard to severe accidents affecting light water reactors is clearly outlined; its main aim is to take all possible measures to optimize control of the most severe accidents that can occur