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:
efines the boundary without giving any implication of system operating pressure. As such, the term “reactor coolant boundary” is applicable to non-LWRs that operate at either low or high pressure. The second paragraph addresses residual heat removal system redundancy. APPENDIX A. ADVANCED REACTOR DESIGN CRITERIA Appendix A to DG-1330, Page A-14 IV. Fluid Systems Criterion ARDC Title and Content NRC Rationale for Adaptions to GDC The GDC reference to electric power was removed. Refer to ARDC 17 concerning those systems that require electric power. 35 Emergency core cooling. A system to provide sufficient emergency core cooling shall be provided. The system safety function shall be to transfer heat from the reactor core such that effective core cooling is maintained and fuel damage is limited. Suitable redundancy in components and features and suitable interconnections, leak detection, isolation, and containment capabilities shall be provided to ensure that the system safety function can be accomplished, assuming a single failure. In most advanced reactor designs, a single system (i.e the residual heat removal system) is provided to perform both the residual heat removal and emergency core cooling functions. In this case, the single system would be designed to meet the requirements of ARDC 34 and ARDC 35. (for more discussion see NUREG-0968 (Ref. 5) and NUREG-1368 (Ref. 4)) However, the staff 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. Effective core cooling may include maintaining the primary coolant boundary in a condition necessary for adequate postulated accident heat removal. The staff’s approach to provide two separate criteria is