Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

About Definition and Practical Application of Probabilistic Safety Indicators Related to Large Accidental Release

3/18/2024 2024 - #01 Global safety, reliability and diagnostics of nuclear power installations

Lyubarskiy A.V. Tokmachev G.V. Mihalev A.V. Kuzmina I.B.

DOI: https://doi.org/10.26583/npe.2024.1.05

UDC: 621.039.58

The probability of a large early release is one of the safety indicators that reflects the risk of fatalities during an accident at a nuclear power plant. Despite the fact that this indicator is very significant, it isn’t defined in the federal rules and regulations of the Russian Federation. The article analyzes the experience of determining radiation safety goals for nuclear power plants in the US NRC, taking into account the statistical data of the specific country under consideration (USA), which includes quantitative health objectives (QHOs) and associated safety goals (SG). A conclusion has been made about the sustainable nature of the goals identified using the NRC approach. A critical analysis of the set of indicators allowed us to conclude that it is necessary to improve the methodology for assessing the safety goals based on the specified SG, taking into account the specifics of NPP projects, regional characteristics, phases of accident development and other factors. The article outlines the proposed approaches to determining SG’s based on probabilistic targets – quantitative values of QHO1 and QHO2 for the Russian Federation. A definition of a «large early release» is formulated and criteria for its achievement are proposed, taking into account measures to protect the population living within the protective action-planning zone.

Thus, when assessing the degree to which these goals are achieved in practice, it is proposed to take into account not only the likelihood of a large release during an accident at a nuclear power plant, but also measures aimed at protecting the population, in particular evacuation. In this case, early deaths occur only when the population is not evacuated before the critical health dose loads from the release are reached.


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health goals probabilistic safety goals large early release measures to protect the population

Link for citing the article: Lyubarskiy A.V., Tokmachev G.V., Mihalev A.V., Kuzmina I.B. About Definition and Practical Application of Probabilistic Safety Indicators Related to Large Accidental Release. Izvestiya vuzov. Yadernaya Energetika. 2024, no. 1, pp. 59-73; DOI: https://doi.org/10.26583/npe.2024.1.05 (in Russian).