Document: NRC Regulatory Guide
Document ID: 9c99a4b7-8619-41f0-b716-262bfdb03941
Document Type: regulatory_guide
Title: Developing Principal Design Criteria for Non-Light Water Reactors + HISTORY - HISTORY 02/2017 – DG-1330 , Proposed Revision 0
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1630/ML16301A307.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.232
CFR Part: 
CFR Title: 

Content:
ormance of the full operational sequence that brings the system into operation, including operation of any associated systems and interfaces necessary to transfer decay heat to the ultimate heat sink. acknowledges that this may not be the case for every advanced reactor design. Therefore, to allow current and future non-LWR designers the flexibility to provide a single system or multiple systems to perform residual heat removal and emergency core cooling, the staff decided to keep the ARDC 34 and ARDC 35 separate in lieu of combining them into a single criterion. The staff’s approach to provide two separate criteria is consistent with the approach taken in the LWR GDCs. The ARDC has slightly different wording than the GDC to clarify the scope of the criterion. Any system, or portions of a system, credited with an emergency core cooling function during postulated accidents (for example, a system that performs both the residual heat removal function and the emergency core cooling function) would need to meet ARDC 37. Specific mention of “pressure” testing has been removed yet remains a potential requirement should it be necessary as a component of “…appropriate periodic functional testing...” of cooling systems. A non-leaktight system may be acceptable for some designs provided that (1) the system leakage does not impact safety functions under all conditions, and (2) defense in depth is not impacted by system leakage. “Active” has been deleted in item (2) as appropriate operability and performance system component testing are required, regardless of an active or passive nature. Reference to the operation of applicable portions of the protection system, cooling water system, and power transfers is considered part of the more general “associated systems.” Together with the APPENDIX A. ADVANCED REACTOR DESIGN CRITERIA Appendix A to DG-1330, Page A-17 IV. Fluid Systems Criterion ARDC Title and Content NRC Rationale for Adaptions to GDC ultimate heat