Document: NUREG-0800
Document ID: 89a50aec-b387-4999-9c8e-3b8e4f289a55
Document Type: srp
Title: Revision 3 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0708/ML070800027.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3
CFR Part: 
CFR Title: 

Content:
tems and essential systems and components, or (2) in fluid systems having dual functions (i.e., required to operate during normal plant conditions as well as to shut down the reactor). In these cases, redundant design features that are separated or otherwise protected from postulated piping failures, or additional protection, should be provided so that the effects of postulated piping failures are shown by the analyses and guidelines of Section B.3 to be acceptable. Additional protection may be provided by designing or testing essential systems and components to withstand the environmental effects associated with postulated piping failures. 2. Design Features a. Essential systems and components should be designed to meet the seismic design requirements of Regulatory Guide (RG) 1.29. b. Protective structures or compartments, and other protective measures should be designed in accordance with the following: Protective structures or compartments needed to implement Section B.1 should BTP 3-3-4 Revision 3 - March 2007 be designed to seismic Category I requirements. The protective structures should be designed to withstand the effects of a postulated piping failure (i.e., pipe whip, jet impingement, pressurization of compartments, water spray, and flooding, as appropriate) in combination with loadings associated with the design basis earthquake within the respective design load limits for structures. c. Fluid system piping in containment penetration areas should be designed to meet the break exclusion provisions contained in item 2.A(ii) of BTP 3-4. d. Piping classification as recommended by RG 1.26 should be maintained without change until beyond the outboard restraint. If the restraint is located at the isolation valve, a classification change at the valve interface is acceptable. 3. Analyses and Effects of Postulated Piping Failures a. To show that the plant arrangement and design features provide the necessary protection of essential systems and components, piping