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:
of the boundary. The system shall be designed to ensure that the system safety function can be accomplished using the piping, pumps, and valves used to maintain reactor coolant inventory during normal reactor operation. ARDC 33 was relabeled as “inventory maintenance” to provide more flexibility for advanced reactor designs. The first sentence is modified so that it ends with “...shall be provided as necessary” and is combined with the second sentence “as necessary to ensure…” (without the opening phrase “The system safety function shall be”) to recognize that the inventory control system may be unnecessary for some designs to maintain safety functions that ensure fuel design limits are not exceeded. “Reactor coolant pressure boundary” has been relabeled as “reactor coolant boundary” to create a more broadly applicable non-LWR term that defines 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 staff maintained the words “system safety function” of GDC 33 because reactor coolant inventory maintenance may be necessary in some designs to support residual heat removal, which is a safety function. If not required for maintaining residual heat removal capability, the qualifier “as necessary” in the first sentence would apply. For example, if all small breaks or leaks would result APPENDIX A. ADVANCED REACTOR DESIGN CRITERIA Appendix A to DG-1330, Page A-13 IV. Fluid Systems Criterion ARDC Title and Content NRC Rationale for Adaptions to GDC in reactor coolant inventory levels such that the residual heat removal function would still be performed, and the fuel design limits met, no safety function would be associated with the inventory maintenance system. The GDC reference to electric power was removed. Refer to ARDC 17 concerning those systems that require electric power. 34 Residual heat removal.