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:
e acceptance criteria. Certain selective implementations may not require dose calculations, as described in Regulatory Position 1.3 of this guide. 4.1 Offsite Dose Consequences The licensee should use the following assumptions in determining the TEDE for persons located at or beyond the EAB: a. The dose calculations should determine the TEDE. TEDE is the sum of the effective dose equivalent (for external exposures) (EDEX) and the committed effective dose equivalent (for internal exposures) (CEDE). The calculation of these two components of the TEDE should consider all radionuclides, including progeny from the decay of parent radionuclides that have significant dose consequences and significant released radioactivity.12 b. The exposure-to-CEDE factors for inhalation of radioactive material should be derived from the data provided in International Commission on Radiological Protection (ICRP) Publication 30, “Limits for Intakes of Radionuclides by Workers,” issued in 1979 (Ref. 28). Table 2.1 of Federal Guidance Report 11, “Limiting Values of Radionuclide Intake and Air Concentration and Dose Conversion Factors for Inhalation, Submersion, and Ingestion,” issued in 1988 (Ref. 29), provides 12 The prior practice of basing inhalation exposure on only radioiodine and not including radioiodine in external exposure calculations is not consistent with the definition of TEDE and the characteristics of the revised source term. DG-1389, Page 24 tables of conversion factors acceptable to the NRC staff. The factors in the column headed “effective” yield doses that correspond to the CEDE. c. Table III.1 of Federal Guidance Report 12, “External Exposure to Radionuclides in Air, Water, and Soil,” issued in 1993 (Ref. 30), provides external effective dose equivalent (EDE) conversion factors acceptable to the NRC staff. The factors in the column headed “effective” yield doses that correspond to the EDE. d. No correction should be made for depletion of the effluent