The improvement of probabilistic methods for assessment of operational occurrences of nuclear power plants using probabilistic safety analysis

The improvement of probabilistic methods for assessment of operational occurrences of nuclear power plants using probabilistic safety analysis

Federal rules and regulations in the field of atomic energy use, which require the analysis of operational events at nuclear power plants, including the use of probabilistic safety analysis results, are represented.
It was established that the recommendations of Nuclear Safety Guide RB-104-16 “Recommendations for use of probabilistic safety assessment in evaluating nuclear power plants operational disturbances”, developed in support of the above requirements, are generally harmonized with international documents. However, they require clarification and supplementation, for example, in terms of assessing the significance of operational occurrences leading to initiating events and which are considered in the second-level probabilistic safety analysis.
Based on the results of an analysis of Russian and international experience in assessing operational occurrences in the operation of nuclear power plants, proposals have been developed to improve probabilistic methods for assessing operational occurrences, including clarifying the list of probabilistic indicators, clarifying the procedure for calculating them using the probabilistic model for nuclear power plant unit, as well as clarifying criteria for assessing the significance of operational occurrences on the impact on safety.
It was noted that taking these proposals into account when updating RB-104-16 will ensure the correct assessment and categorization of operational occurrences in the operation of nuclear power plants, which, in turn, will facilitate the adoption of corrective and regulatory measures to ensure the safety of nuclear power plants.

► Keywords: probabilistic safety analysis, operational occurrence of nuclear power plant, probabilistic model for nuclear power plant unit.

Article language: Russian. Pp. 47–55. [in Russian]. DOI: 10.26277/SECNRS.2025.117.3.005.