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:
o steam power system, and systems similar to the PRISM Direct Reactor Auxiliary Cooling System (DRACS). A paragraph from NUREG 1368 (page 3-41) was added describing the characteristics of the residual heat removal working fluid and its associated operating pressure. This SFR-DC has been worded to explain that an intermediate coolant system may be used if the primary coolant is not chemically compatible with the energy conversion system coolant. A single passive barrier is adequate defense in depth when the heat removal working fluid is chemically compatible with the primary coolant, such that postulated leakage between the two systems does not result in the failure of any intended safety function of any SSC important to safety or cause fuel design limits to be exceeded. An example is a heat removal system with liquid sodium potassium (NaK). A liquid sodium primary coolant system that is contaminated with NaK may have phase changes (e.g., solidification, boiling) at different temperatures, without adversely affecting the overall system. The postulated leakage may be based upon a leak-before-break analysis or the ability to detect leakage between the primary and intermediate coolant systems. If the working fluids are not chemically compatible, at least two passive barriers must separate the two systems. The higher pressure requirement is to ensure any leakage in the interface between the two systems does not result in a release of APPENDIX B. SODIUM-COOLED FAST REACTOR DESIGN CRITERIA Appendix B to DG-1330, Page B-34 VII. Additional SFR-DC Criterion SFR-DC Title and Content NRC Rationale for Adaption to GDC radioactive primary coolant to the nonradioactive part of the heat transport system. A sentence has been added to explain that this differential pressure requirement must be satisfied during AOOs and design-basis accidents, as well as during normal operating and shutdown conditions. 79 Cover gas inventory maintenance. A system to maintain cover gas inventory shall