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:
measured at three different fluence values for a material, then no surveillance tests are required for that material. The remaining steps of this procedure may be ignored and the ETC in 10 CFR 50.61a (Equation (5)) may be used. ii. If there are three of more ΔT30 values measured at three different fluence values for a material, then statistical surveillance tests are required for this material. The remaining steps of this procedure should be followed. (c) For all materials remaining after Step (1)(b)(ii), assemble the following information: • heat identification • plant identification • capsule identification • product form • notch orientation • the unirradiated reference temperature, RTNDT(U) • ΔT30 • Charpy-V notch energy data used to estimate ΔT30 • fluence • operating time • cold leg temperature under normal full-power operating conditions (Tc) o Note: Tc (°F) is determined as the time-weighted average coolant temperature of the reactor coolant system cool leg covering the time period from the start of full power operation through the end of licensed operation. • copper (Cu) content • nickel (Ni) content • phosphorus (P) content • manganese (Mn) content • citation The values of, Cu, Ni, P, and Mn must represent the best estimate values for the material (10 CFR50.61a(f)(3)). For a plate or forging, the best estimate value is normally the mean of the measured values for that plate or forging. For a weld, the best estimate value is normally the mean of the measured values for a weld deposit made using the same weld wire heat number as the critical vessel weld. If these values are not available, either the upper limiting values given in the material specifications to which the vessel material was fabricated, or conservative estimates (i.e., mean plus one standard deviation) based on generic data should be used. Step 2: Perform Statistical Assessments of the Surveillance Data For each material remaining after Step (1)(b)(ii),