Izvestiya vuzov. Yadernaya Energetika

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

Large Early Accidental Release – What Is It and Is It Needed in RF Standards?

12/20/2024 2024 - #04 Global safety, reliability and diagnostics of nuclear power installations

Lyubarskiy A.V. Tokmachev G.V. Mikhalev A.V.

DOI: https://doi.org/10.26583/npe.2024.4.07

UDC: 621.039.58

The federal norms and regulations of the Russian Federation provide a definition of a large accidental release, but there are no requirements for assessing the probability of a large early accidental release (LER). This indicator reflects the risk of early fatalities in a nuclear power plant accident and is a generally recognized significant indicator of nuclear power plant safety, used in a number of IAEA member countries, but ignored in the Russian Federation. The article analyzes the domestic regulatory practice of using the concept of a LER when conducting a probabilistic safety assessment (PSA). An analysis of IAEA documents was carried out regarding the definition of large early and late releases and requirements for assessing the risk of the population living in the area of the nuclear power plant. It is shown that the definition of LER in Russian PSA is incomplete, does not correspond to the definitions in IAEA standards and safety goals and requires clarification and addition. Based on the results of the analysis, a definition of large late and early accidental releases was formulated for use in PSA in the Russian Federation and possible criteria for their achievement were proposed both with and without measures to protect the population living within the protective action planning zone. The article shows the approaches of the Turkish Republic in terms of determining early and large releases, which are more consistent with IAEA documents. The article makes a number of important conclusions, regarding the need for a more detailed definition of LER, clarification of target probabilistic guidelines (according to new definitions) and clarification of dose criteria in Russian regulatory documents and PSA. The proposed changes will lead to a more realistic assessment of the population’s risk and will allow the results of the PSA to be used to optimize protective actions.

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large accidental release early and late large accidental release protective action planning area measures to protect the population criteria evacuation

Link for citing the article: Lyubarskiy A.V., Tokmachev G.V., Mikhalev A.V. Large Early Accidental Release – What Is It and Is It Needed in RF Standards?. Izvestiya vuzov. Yadernaya Energetika. 2024, no. 4, pp. 81-94; DOI: https://doi.org/10.26583/npe.2024.4.07 (in Russian).

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