Document: NRC Regulatory Guide
Document ID: b3da4d67-03d8-4f52-b04b-8e76d142c857
Document Type: regulatory_guide
Title: Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light Water Reactors + HISTORY - HISTORY 05/2019 – Issued DG-1353 , Proposed Revision 0
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1831/ML18312A242.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.233
CFR Part: 
CFR Title: 

Content:
porting guides and standards, these DBEHLs will be informed by a 7 An example is the anchor point at an event sequence frequency of 5x10-7 per plant year and total effective dose equivalent at the EAB of 750 rem for the 30-day period following the onset of a potential release. This anchor point is used to define a sliding F-C target in the region of potential low frequency, high consequence scenarios for use in assessing the importance of SSCs and other measures to provide DID. A traditional measure used to assess risk in the low frequency, high consequence domain is the NRC’s safety goals. However, the anchor point is not intended to directly represent the quantitative health objectives (QHOs) for either early or latent health effects. The methodology described in NEI 18-04 includes a separate assessment of a design against the QHOs for the integrated risks over all the LBEs. DG-1353, Page 14 probabilistic external hazards analysis and included in the PRA after the design features that are included to withstand these hazards are defined. If applicants propose methods to identify DBEHLs that the NRC staff has not previously reviewed and approved, the staff would review the proposed methodologies on a case-by-case basis. An applicant may need to reconcile a probabilistic approach to assessing external hazards with the use of applicable consensus standards for the design and construction of safety- significant SSCs d. NEI 18-04 describes how the application of a single-failure criterion is not deemed necessary for the designs using the methodology because advanced non-LWRs will employ a diverse combination of inherent, passive, and active design features to perform the required safety functions across layers of defense and will be subjected to an evaluation of DID adequacy. The process described in NEI 18-04 includes assessing event sequences (including reliability and availability of SSCs and combinations of SSCs) over a wide range of frequencies and establishing