Document: NRC Regulatory Guide
Document ID: 4d46a966-d280-43da-9b03-8b0abe7b29ce
Document Type: regulatory_guide
Title: Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2120/ML21204A065.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.183
CFR Part: 
CFR Title: 

Content:
nform its development of this RG, the NRC considered IAEA Safety Requirements and Safety Guides pursuant 3 The NUREG-1465 source terms have often been referred to as the “revised source terms.” In recognition that additional source terms may be identified in the future, 10 CFR 50.67 addresses “alternative source terms.” This regulatory guide endorses a source term derived from SAND-2011-0128 and provides guidance on the acceptable attributes of other ASTs. DG-1389, Page 7 to the Commission’s International Policy Statement (Ref. 13) and Management Directive and Handbook 6.6, “Regulatory Guides” (Ref. 14). The NRC staff did not identify any IAEA Safety Requirements or Guides with enough detailed information relevant for use by Part 50 and 52 licensees and applicants as related to the topic of this RG. DG-1389, Page 8 C. STAFF REGULATORY GUIDANCE Section C, “Staff Regulatory Guidance,” and the appendices of this RG contain regulatory positions that establish a method acceptable to the staff of the U.S. NRC for complying with regulations for DBA dose consequence analysis using an AST. 1. Implementation of Accident Source Term 1.1 Generic Considerations As used in this guide, the AST is an accident source term that is derived principally from SAND- 2011-0128 and differs from the TID-14844 and NUREG-1465 source terms used in the original and revised design and licensing of operating reactor facilities. ASTs may be used for advanced LWRs under 10 CFR Part 50 and 10 CFR Part 52 and for operating reactors under 10 CFR 50.34 and 10 CFR 50.67. This guide identifies an AST that is acceptable to the NRC staff and significant characteristics of other source terms that may be found acceptable. While the staff recognizes several potential uses of an AST, it is not possible to foresee all possible uses. Licensees may pursue technically justifiable uses of the ASTs in the most flexible manner in license amendments so long as they are compatible with maintaining a