Advanced nuclear power plant regulation using risk-informed and performance-based methods

This paper proposes and discusses implications of a largely probabilistic regulatory framework using best-estimate, goal-driven, risk-informed, and performance-based methods. This framework relies on continuous probabilistic assessment of performance of a set of time-dependent, safety-critical systems, structures, components, and procedures that assure attainment of a broad set of overarching technology-neutral protective, mitigative, and preventive goals under all phases of plant operations. In this framework acceptable levels of performance are set through formal apportionment so that they are commensurate with the overarching goals. Regulatory acceptance would be the based on the confidence level with which the plant conforms to these goals and performance objectives. The proposed framework uses the traditional defense-in-depth design and operation regulatory philosophy when uncertainty in conforming to specific goals and objectives is high. Finally, the paper discusses the steps needed to develop a corresponding technology-neutral regulatory approach from the proposed framework.