ESTABLISHING EMERGENCY PLANNING ZONE SIZE REQUIREMENTS FOR SMALL MODULAR REACTORS BASED ON PREDICTED RADIOLOGICAL DOSE CONSEQUENCES FROM HYPOTHETICAL SEVERE ACCIDENTS

摘要

Small Modular Reactors (SMRs) are claimed to possess superior safety characteristics compared to large water-cooled plants. One way to assess the safety of a nuclear power plant is to predict the radiological dose consequence from a hypothetical "worst-case" accident. It has been postulated that the predicted public dose consequence from such an accident would be a key input to determining reasonable size requirements for an Emergency Planning Zone (EPZ) around the plant. To that end, public dose consequences from hypothetical severe accidents in four SMR types were evaluated using industry standard methods. Based upon informed and conservative estimates of severe accident source terms from these SMRs, the predicted dose consequences were sufficiently low, compared to an accident at a contemporary large plant, to support this argument for smaller EPZs. This was especially the case for advanced reactor types that possess the inherent capability to chemically retain most fission products.