Ma. Caruso et al., An approach for using risk assessment in risk-informed decisions on plant-specific changes to the licensing basis, RELIAB ENG, 63(3), 1999, pp. 231-242
This paper discusses an acceptable approach that the US Nuclear Regulatory
Commission staff has proposed for using Probabilistic Risk Assessment in ma
king decisions on changes to the licensing basis of a nuclear power plant.
First, the overall philosophy of risk-informed decision-making, and the pro
cess framework are described. The philosophy is encapsulated in five princi
ples, one of which states that, if the proposed change leads to an increase
in core damage frequency or risk, the increases must be small and consiste
nt with the intent of the Nuclear Regulatory Commission's Safety Goal Polic
y Statement. The second part of the paper discusses the use of PRA to demon
strate that this principle has been met. The discussion focuses on the acce
ptance guidelines, and on comparison of the PRA results with those guidelin
es. The difficulties that arise because of limitations in scope and analyti
cal uncertainties are discussed and approaches to accommodate these difficu
lties in the decision-making are described. (C) 1999 Elsevier Science Ltd.
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