Document: NRC Regulatory Guide
Document ID: da2e0703-3488-44b0-b6d0-089aac7cae3d
Document Type: regulatory_guide
Title: Format and Content of Plant-Specific Pressurized Thermal Shock Safety Analysis Reports for Pressurized Water Reactors
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740028.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.154
CFR Part: 
CFR Title: 

Content:
and *To avoid confusion among several (preexisting) s l i g h t l y d i f f e r e n t d e f i n i t i o n s of RTNDT, !$ 50.61 contains i t s own d e f i n i t i o n o f an RTNDT (called RTpTS) t o be used when comparing plant-speci f i c vessel materi a1 properties w i t h the PTS screening c r i t e r i o n . operation are necessary t o prevent potential f a i l u r e o f the reactor vessel as a r e s u l t o f postulated PTS events i f continued operation beyond the screening c r i t e r i o n i s a1 lowed. These analyses must include the effects o f a1 1 corrective actions the licensee believes necessary t o achieve an acceptable PTS-related r i s k f o r continued operation o f the plant. The f i n a l objective o f the plant- specific PTS study, therefore, i s t o j u s t i f y continued operation o f the plant by demonstrating t h a t the 1 i kel i hood o f a through-wal 1 crack during continued operation i s acceptably low. The study must include calculation, f o r the re- mainder o f plant 1 i f e , o f the expected frequency o f through-wall cracks due t o PTS . I n calculating these results, it w i l l be necessary to: O I d e n t i f y the dominant accident sequences. O I d e n t i f y operator actions, control actions, and plant features impor- t a n t t o PTS. O Estimate the effectiveness o f potential corrective actions i n reduc- i ng the expected frequency o f through-wal 1 cracks. O I d e n t i f y the sources and approximate magnitude o f the major uncertain- t i e s and t h e i r effects on the conclusions. O Present and j u s t i f y the licensee's proposed program f o r corrective measures. I \ O Present and j u s t i f y the licensee's proposed basis f o r continued opera- t i o n a t embrittlement level s above the screening criterion. This must include comparison with the acceptance c r i t e r i a described be1 ow o f the PTS-related through-wall crack frequency with corrective actions implemented as necessary. S t a f f Review o f