Design of a Novel Decision-Making Tool for the Analysis of Protective Actions During a Radiological Release

摘要

The design and operation of nuclear power plants employs the philosophy of defense-in-depth to prevent and mitigate accidents and the release of radionuclides to the environment. Defense-in-depth includes the use of access controls, physical barriers, redundant and diverse safety systems, and emergency preparedness and response. As the final layer in a robust defense-in-depth strategy, emergency plans ensure that protective actions can and will be taken to protect the public in the event of a radiological release.Protective actions for radiological events include evacuation and sheltering-in-place, the same types of action taken in response to other types of hazards. For radiological events, these actions are informed by protective action guides (PAG) set by the U.S. Environmental Protection Agency (EPA) [1]. Actions to minimize or avoid dose are recommended for a projected dose of 1-5 rem to the whole body during the first 96 hours of exposure [1]. Some hazards, such as hurricanes and fires, are immediately dangerous to life and health, and the need for protective actions is obvious. But for radiological events, protective actions are triggered at projected dose levels based on a hypothetical population risk of cancer, driven by assumptions of the linear no-threshold (LNT) hypothesis. Because an evacuation carries its own risk, it is important to examine if the risks are appropriately balanced.