Document: NRC Regulatory Guide
Document ID: 3df13dae-14ee-4f25-95b4-1cedf617ae15
Document Type: regulatory_guide
Title: Regulatory Guidance on the Alternate Pressurized Thermal Shock Rule + HISTORY - HISTORY 03/2015 – DG-1299 , Proposed Revision 0
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1405/ML14056A011.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.230
CFR Part: 
CFR Title: 

Content:
tep A should be evaluated for axial flaw surface connection. Any flaws with a through-wall extent greater than or equal to 0.075 inch, axially oriented and located at the clad-to-base metal interface, should be verified to not be connected to the RPV inner surface using surface examination techniques capable of detecting and characterizing service-induced cracking of the RPV cladding. Eddy current and visual examinations methods are acceptable to the staff for detection of cladding cracks. An appropriate quality standard shall be implemented to ensure these examinations are effective at identification of surface cracking as required by 10 CFR 50 Appendix B, Criterion IX “Control of Special Processes,” which requires in part, that measures shall be established to assure that special ΔT30(MEAS) – ΔT30(ETC,mean) φt ΔT30 φt Mean ETC Prediction Surveillance Measurements ETC Confidence Bounds ΔT30(MEAS) – ΔT30(ETC,mean) φt ΔT30 φt Mean Test Failure rmean rmax ADJ = rmean - rmax Datum causing outlier test failure φtEVAL φtLOW Low Fluence Outlier Test Failure DG-1299, Page 15 processes, including nondestructive testing, are controlled and accomplished by qualified personnel using qualified procedures in accordance with applicable codes, standards, specifications, criteria, and other special requirements. Appropriate quality standards for implementation of surface examinations are identified in the ASME Code Section XI “Rules for Inservice Inspection of Nuclear Power Plant Components” and/or Section V “Nondestructive Examination.” Step C: If the results of Step B are acceptable, the plant-specific flaw data should be evaluated for acceptability in accordance with ASME Code, Section XI, Table IWB-3510-1 flaw acceptance standards. Step D: If the results of Step C are satisfactory, or (if applicable) the results of Step F are acceptable, the plant-specific flaw data should be compared to Tables 2 and 3 of 10 CFR 50.61a. A specific example of how this