Document: NRC Regulatory Guide
Document ID: 535957c7-1203-410d-b709-8e4d381f00de
Document Type: regulatory_guide
Title: Measurements of Radionuclides in the Environment, Analysis of I-131 in Milk
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML1335/ML13350A246.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.3
CFR Part: 
CFR Title: 

Content:
ted with tile measurement follows: Wl of ppt. mg Chem ical yield = ,, .8 I 14.83" F'nh! ppt is not Stoichii n ntrically Pdlt. and determined weight of PdIc for 10 ml! of I. I. Chemical yi!J 2. Counter efficiency 3. Counter hackground 4. Counting time 5. Radioactive decay 6. Sample net coun:s Gross counts for I 000-min interval The net counts Standard deviation Net count with error limit Net pCi/liter this value is a deIermined empirical yield l'r 100u5 r1c, a ry: 14.83 mgi% i', Ihw = 0.78 7 0.35 0 0.6 cpm = 1000 minutes - 8.05 days - 0.6- cpn (fIor a I-lialf-life decay period) = (background cpm + net cpm) (counting tin..) = (0.6 + 0.6))1000 = 1200 - 1200 - 600 = 600 corrnts per 1000 minutes or 0.6 cpnm = gross counts + background counts 1 2600++600=42 - 600 ± 42 (net counts) (factor for protein-bound fraction) 0 (count time)(chem yield)(counter efflt sample vol hIdecay )(dpil/pCi) (600 ± 42) (1.05) ( 1000)(0.78)(0.35)(4)(0.50)(2.22) = 0.5 pCi/liter with standard deviation of ± 7r;" 4.3-5