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:
acity, capability, and reliability to ensure vital safety functions are maintained. The emphasis is placed on requiring reliability of power sources rather than prescribing how such reliability can be attained. Reference to onsite vs. offsite electric power systems was deleted to APPENDIX A. ADVANCED REACTOR DESIGN CRITERIA Appendix A to DG-1330, Page A-5 II. Multiple Barriers Criterion ARDC Title and Content NRC Rationale for Adaptions to GDC anticipated operational occurrences and (2) vital functions that rely on electric power are maintained in the event of postulated accidents. The onsite electric power systems shall have sufficient independence, redundancy, and testability to perform their safety functions, assuming a single failure. provide for those reactor designs that do not depend on offsite power for the functioning of SSCs important to safety. Text related to “…supplies, including batteries, and the onsite distribution system,” was deleted to allow increased flexibility in the design of offsite power systems for advanced reactor designs. However, it is still expected that such onsite systems must remain capable of performing assigned safety functions during accidents as a condition of requisite reliability. The existing single switchyard allowance remains available under ARDC 17. If a particular advanced design requires the use of GDC single switchyard allowance wording, the designer should look to GDC 17 for guidance when developing PDC. If electrical power is not required to permit functioning of SSCs important to safety, the requirements in the ARDC are not applicable to the design. In this case, the functionality of SSCs important to safety must be fully evaluated and documented in the design bases. “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