The modern approach to methodology of probabilistic safety analysis

The methodology of probabilistic safety analysis, which is widely used for solving the safety problems in the process of design and operation at NPPs with the WWER type reactor is briefly described. The methodology includes general probabilistic model describing arising of emergency states with exceeding the preset value of maximum credible consequences at NPPs, list of probabilistic safety indexes, definition of the basic tasks, methods, approaches, data bases and computer codes required for creation of detailed probabilistic models for determination of the full variety of emergence states and making the qualitative calculations, as well as the approach to estimation of safety level basing on the results of analysis made