Document: NRC Regulatory Guide
Document ID: c0dbb594-6262-4b83-96b1-366758ad9676
Document Type: regulatory_guide
Title: Interim Licensing policy on as low as Practicable for Gaseous Radiodine Releases from Light-Water-Cooled Nuclear Power Reactors (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1229/ML12298A137.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.42
CFR Part: 
CFR Title: 

Content:
maximum thermal power level (MWt) evaluated for safety considerations in the Safety Analysis Report. 2. Plant Capacity Factor - 80%. 0 1. 42-A4 3. Equilibrium Primary Coolant Radioiodine Concentration - The 1-131 concentration in the primary coolant is assumed to be 5 x 10-3 pCi/g, independent of power level. 4. Reactor Building Leakage Rate (gaseous source term only) Use 500 lb/hr at primary coolant activity and a PF of 0.001 for radioiodine. 5. Radwaste Building (gaseous source term only) - The release of radioiodine in gaseous effluent is negligible (<10-4 Ci/yr of iodine-131). 6. Turbine Building Steam Leakage Rate (gaseous source term only) a. If no special design features are provided to reduce the leakage from steam line valves, use a leakage rate of 1700 lb/hr and PF of 1 for radioiodine. b. If special design features are provided to reduce leakage from the "Stop, Control, and Bypass" valves (24 inches and larger) and no others, use a leakage rate of 1350 lb/hr and a PF of 1 for radioiodine. c. If special design features are provided to reduce the leakage from all steam line valves 2-1/2 in. and larger, use a leakage rate of 340 lb/hr and a PF of 1 for radioiodine. 7. Turbine Gland Seal Steam Leakage Rate (gaseous source term only) Use 0.1% of the main steam flow and a decontamination factor(DF) of 100 for radioiodine across the turbine gland seal steam con- denser. If clean steam is supplied to the gland seal, the radio- iodine source term is negligible (<10-4 Ci/yr). If sealing steam 1.42-A5 0 is supplied from the condensate storage tanks, 1 x 10-6 times the main steam flow should be used. 8. Partition (PF) and Decontamination Factors (DF) for Radioiodine PF Reactor Vessel, Internal Partition 0.01 DF Main Condenser Air Ejector 200 Recombiner/Condenser 100 Charcoal Adsorber 10 9. Decontamination Factors (DF) for Demineralizers Note: For two demineralizers in series, the DF for the second demineralizer is given in parentheses. DF (Anion) 0 Mixed Bed (H+ OH-)