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:
ons made in the facility’s PRA, the licensee should evaluate the impact on the existing PRAs. 7 In performing screenings and evaluations pursuant to 10 CFR 50.59, it may be necessary to compare dose results (figure-of-merit) expressed in terms of whole body and thyroid with results expressed in terms of TEDE. Either figure-of-merit represents different systems of dosimetry. There is no methodology that converts the figures-of-merit between systems. Therefore, to calculate the desired figure-of-merit, the appropriate dosimetry methodology (i.e., dose-conversion-factors) must be applied. DG-1389, Page 15 Consideration should be given to the risk impact of proposed implementations that seek to remove or downgrade the performance of previously required engineered safeguards equipment on the basis of the reduced postulated doses. The NRC staff may request risk information if there is a reason to question adequate protection of public health and safety. The licensee may elect to use risk insights in support of proposed changes to the design basis that are not addressed in currently approved NRC staff positions. For guidance, refer to RG 1.174, “An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis,” issued January 2018 (Ref. 20). For additional information, refer to LIC-206, “Integrated Risk-Informed Decision-Making for Licensing Reviews,” dated June 26, 2020 (Ref. 21), regarding how the staff performs integrated risk-informed decision-making for licensing reviews. 1.5 Submittal Requirements and Information According to 10 CFR 50.90, “Application for Amendment of License, Construction Permit, or Early Site Permit,” an application for an amendment must fully describe the changes desired and should follow, as far as applicable, the form prescribed for original applications. RG 1.70, Revision 3, “Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants (LWR