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:
. . . . . . . . . . . 8.4 Plant Modifications . . . . . . . . . . . . . . . . . 8.5 I n S i t u A n n e a l i n g . . . . . . . . . . . . . . . . . . CHAPTER 9 FURTHER ANALYSES . . . . . . . . . . . . . . . . . . . . CHAPTER 10 RESULTS AND CONCLUSIONS REGARDING PTS ANALYSES . . . . . . 10 . 1 Summary o f Analysis . . . . . . . . . . . . . . . . . 10.2 Basis f o r Continued Operation . . . . . . . . . . . . REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . REGULATORY ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . INTRODUCTION / Background and Purpose o f This Guide The pressurized thermal shock (PTS) rule, § 50.61 o f 10 CFR Part 50 issued on July 23, 1985 (50 FR 29937), establishes a screening c r i t e r i o n based on reactor vessel n i l - d u c t i l i t y - t r a n s i t i o n temperature (RTNDT) The screening c r i t e r i o n was establ ished a f t e r extensive industry and NRC analyses regarding the likelihood o f vessel f a i l u r e due t o PTS events i n pressurized water reactors (PWRs). The analyses were applied generically and contained conservative assumptions t o make the results bounding f o r any PWR. Based on the results, the NRC concluded t h a t the r i s k due t o PTS events i s acceptable a t any p l a n t so long as the RTpTSX o f the reactor pressure vessel remains be1 ow the screening c r i t e r i o n . Extensive safety analyses are required by the r u l e for any p l a n t t h a t wishes t o operate with RTpTS values above the screening c r i t e r i o n . The recom- mended methods t o be used i n performing the analyses are outlined i n t h i s guide. The purpose o f the analyses i s t o assess the r i s k due t o PTS events f o r proposed operation o f the p l a n t w i t h reactor vessel RTpTS above the screen- ing c r i t e r i o n . Effective 1 year a f t e r the pub1 i c a t i o n o f t h i s regulatory guide, Section 50.61 requires t h a t these analyses be completed 3 years before the screening c r