Document: NUREG-0800
Document ID: f018d9c1-daa9-44c5-b7e9-907bec814455
Document Type: srp
Title: TURBINE BYPASS SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0703/ML070380209.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.4
CFR Part: 
CFR Title: 

Content:
condenser inlet do not need to be classified as seismic category I if the following criteria are met: A. They have been analyzed using a dynamic seismic analysis method to demonstrate their structural integrity under SSE loading conditions. B. All pertinent QA requirements of Appendix B to 10 CFR Part 50 are applied. C. For lines utilized as an MSIV leakage path to the condenser, reliable power sources must be available for control and isolation valves so that a control operator can establish the flow path assuming a single active failure. In addition, the TBS lines and other components utilized as an MSIV leakage path to the condenser are assigned a quality group classification in accordance with the criteria of Branch Technical Position 3-1. Technical Rationale The technical rationale for application of these acceptance criteria to the areas of review addressed by this SRP section is discussed in the following paragraphs: 1. GDC 4 requires that structures, systems, and components important to safety be designed to meet environmental conditions associated with normal operation, maintenance, testing, and postulated accident. However, dynamic effects associated with postulated pipe ruptures in nuclear power plants may be excluded from the design basis when analyses reviewed and approved by the Commission demonstrate that the probability of a rupture in the fluid system piping is extremely low under conditions consistent with the design basis for the piping. Although the turbine bypass system is not classified as a system important to safety, GDC 4 applies to this SRP section because a failure of the TBS or one of its 10.4.4-5 Revision 3 - March 2007 components could have an adverse impact on a structure, system, or component important to safety. Meeting the requirements of this criterion provides a level of assurance that structures, systems, and components important to safety will not be adversely affected by a failure of the turbine bypass system. 2. GDC 34