On the Issue of Dose Criteria Selection for Evaluation of Monitoring Intervention Levels Following a Nuclear Power Plant Accident

The dynamics of radiation doses to the public was predicted for scenarios of the most severe beyond design-basis accidents at Russian nuclear power plants with thermal (VVER-440, VVER-1000, VVER-1200) and fast neutron (BN-800) reactors. The need for protective measures was assessed based on the system of emergency dose criteria from NRB-99/2009. It was shown that the radiological consequences of design-basis accidents essentially depend on the type of reactor facility. In case of a severe accident at the VVER-440 reactor, the radiation doses to the population would exceed the established criteria for the acute period. Radiation impact factors for the public were calculated for the considered accident scenarios. The variability of these indicators is due to the inconsistency in the NRB-99/2009 dose criteria, which determine when the population should be evacuated or resettled from contaminated areas. The study revealed the necessity of enhancing the “emergency” criteria system by incorporating the IAEA recommendations. This will allow the development of standardized approaches for addressing this issue.