CONSIDERATIONS ON THE DIFFERENT ASPECTS OF A NUCLEAR-POWER-PLANTS LIFE

Unlike many other countries, where the nuclear power plants have a fin ite period of time foreseen in their operating licence, the authorizat ion in Belgium is delivered without time limitation but on condition o f a safety reassessment process at definite intervals of ten years. Im portant repairs, replacements and modifications (steam generator repla cement, seismic re-evaluation and requalification, RCS overpressure pr otection and process computers) are mainly associated with these 10-ye ar reviews. Beyond those major changes, the follow-up of equipment is performed on a case-by-case basis. Specific monitoring programmes have been developed for sensible equipment to cope with new loading or deg rading phenomena (erosion-corrosion, intergranular attack stress corro sion, weal; stratification, etc.). The lifetime policy is assessed on a pragmatic case-by-case basis, owing to the variety of plants and cir cumstances, 'generic' solutions are not often applicable. This Belgian approach is put into perspective by contrasting it to a variety of po ssible nuclear power plant life definitions.