Document: NRC Regulatory Guide
Document ID: 96baa826-d3bb-478b-8f38-e74500f6d433
Document Type: regulatory_guide
Title: 06/2009 (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0911/ML091170109.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.21
CFR Part: 
CFR Title: 

Content:
be subtracted based on selected control locations. The doses measured from control and indicator locations should be taken from the same time period. When choosing the appropriate control location(s), licensees should consider the historical variability in doses measured at the control and indicator locations. Several sources contain additional information regarding background subtraction for thermoluminescent dosimeters (Refs. 39, 40, 41, and 42). Methods of determining dose from direct radiation to the maximum exposed individual member of the public may also include extrapolation methods. Licensees must demonstrate compliance with 10 CFR 20.1301(e) for the generally applicable environmental radiation standards promulgated in 40 CFR Part 190. These include the concept of a total dose (to the whole body and to any organ) from all sources related to the uranium fuel cycle. Contributions to the total dose from radioactive effluents (liquid and gaseous) and direct radiation should be included, if applicable. Other sources (e.g., accumulated radioactive materials in offsite ponds or lakes from previous years’ discharges) should also be included, if applicable, when estimating the total dose. However, if the contributions from direct radiation or accumulated radioactivity are generally minor (as evaluated and documented in a licensee technical evaluation as not contributing to the total dose), these contributions need not be included in the total dose evaluation, but the basis for exclusion should be documented. 5.9 Dose Calculations Acceptable dose assessment models, such as those provided in Regulatory Guides 1.109, 1.111, 1.112, “Calculation of Releases of Radioactive Materials in Gaseous and Liquid Effluents from Light- Water-Cooled Power Reactors,” (Ref. 43) and 1.113, should be used to make dose calculations. When calculating organ doses from airborne effluents, contributions from I-131, I-133, tritium, and radionuclides in particulate form with half-lives