Document: NRC Regulatory Guide
Document ID: 377c2606-4b7c-4c7f-997d-37aed1680452
Document Type: regulatory_guide
Title: Performance, Testing, and Procedural Specifications for Thermoluminescence Dosimetry: Environmental Applications + HISTORY - HISTORY 10/2018 – DG-4019 , Proposed Revision 2 11/2014 – Periodic Review of Revision 1 – Revise (Rev. 2)
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML1808/ML18087A169.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.13
CFR Part: 
CFR Title: 

Content:
n outlier. The following are justifications for the removal of outlier dosimeter data: a. abnormal high or low readings on some chips as compared to those on other chips (high standard deviation among chips); b. dosimeters that have been lost and later recovered; c. dosimeters that were annealed at a different time and were not issued with the remaining group of dosimeters; d. a sealed plastic bag ripped open and exposed to weather conditions; DG-4019, Appendix A, Page A-3 e. dosimeters that were damaged by vandalism; and f. known processing problems (bad glow curves, a dosimeter history that suggests poor quality or damage, and poor quality control results). 2. Subtract the extraneous dose from each of the gross field dosimeter results to get the net field dose at each location. 3. Calculate the normalized net field dose at each location to a standard monitoring period (e.g., a 91-day quarter). 4. Perform a qualitative comparison of the normalized net field doses to the baseline background dose for each monitored location. Identify outliers and investigate anomalies. 5. Remove justifiable outliers from the data set, and document the bases for removing the outliers. e. Determine the quarterly FRDs. 1. For each monitored location, first calculate the sum of the baseline background dose plus the dosimetry system’s quarterly MDD (approximately 5 to 6 mrem) (0.05 to 0.06 mSv). Note that the normalized net field dosimeter results at each location must be greater than the MDD value to detect an FRD. 2. For each monitored location, subtract the sum of the baseline background dose and the quarterly MDD from the current quarter normalized field dose. a. If the value is negative, there is no detectable FRD. b. If the value is positive, FRD is detected. 3. If a quarterly FRD is detected, calculate the amount of the FRD. To do so, subtract the baseline background dose from the normalized net field dose. Once a positive FRD is identified, only subtract the baseline background