Document: NUREG-0800
Document ID: e89cc26c-d19a-42b8-818a-fb598c05ccee
Document Type: srp
Title: PLANT DESIGN FOR PROTECTION AGAINST POSTULATED PIPING FAILURES IN FLUID
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340548.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.1
CFR Part: 
CFR Title: 

Content:
. Design Features a. Essential systems and components should be designed to meet the seismic design requirements of Regulatory Guide 1.29. b. Protective structures or compartments, fluid system piping restraints, and other protective measures should be designed in accordance with the following: (1) Protective structures or compartments needed to implement Section B.1 should be designed to seismic Category I require- ments. The protective structures should be designed to with- stand 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 operating basis earthquake and 3.6.1-11 Rev. 2 - October 1990 safe shutdown earthquake within the respective design load limits for structures. Piping restraints, if used, may be taken into account to limit effects of the postulated piping failure. (2) High-energy fluid system piping restraints and protective measures should be designed such that a postulated break in one pipe cannot, in turn, lead to rupture of other nearby pipes or 'components if the secondary rupture could result in consequences that would be considered unacceptable for the initial postulated break. An unrestrained whipping pipe should be considered capable of rendering damage as defined in Subsection III.2. of SRP Section 3.6. c. Fluid system piping in containment penetration areas should be designed to meet the break exclusion provisions contained in item B.L.b of BTP EMEB 3-1. d. Piping classification as required by Regulatory Guide 1.26 should be maintained without change until beyond the outboard restraint. If the restraint is located at the isolation valve, a classifica- tion 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 failures