An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis

The U.S. Nuclear Regulatory Commission (NRC) is re-issuing for public comment draft regulatory guide (DG), DG-1285, ``An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis.'' The guide was initially issued for public comment in 2012 as noticed in the Federal Register under NRC Docket number NRC-2012-0110. Subsequently, the NRC decided to incorporate additional information related to evaluation of the defense-in-depth philosophy that was not included in the original publication of DG-1285. This proposed revision of the guide, Revision 3, includes significant expansion of the guidance on the meaning of, and the process for, assessing the defense-in-depth evaluation factors.