The reliability optimized maintenance applied to the EDF nuclear park

The reliability optimized maintenance is a concept introduced in the 70's to simultaneously control the safety and the maintenance costs. The aim of this concept is to maintain at a high level the safety and the averaged annual availability of the power plant, and, conversely, to reduce the dosimetry and the frequency of accidents. The optimum choices for maintenance should take into account both the safety regulations and a technical-economical analysis. The choice for a maintenance policy depends on the priority given to safety, availability and maintenance costs, and to the performance of materials. The methodology used for the reliability optimized maintenance of the French nuclear park follows three steps: the evaluation of goals (functional and failure mode analyses), the evaluation of performances (failures frequency and probabilistic estimations), and the optimization of maintenance (economic constraints, dosimetry, work safety). The technical goal of this methodology is to permanently apply a preventive maintenance at the correct place using the most suitable techniques. (J.S.). 2 figs., 1 tab