Document: NUREG-0800
Document ID: 0e333e1a-276a-43f1-b2ab-fdf1009c6f92
Document Type: srp
Title: Draft Revision 3 – August 2015
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1422/ML14227A646.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3
CFR Part: 
CFR Title: 

Content:
lve), a terminal end of such a run is the piping connection to this closed valve. 4 See Footnote 2. 5 See Footnote 2. BTP 3-4-6 Draft Revision 3 – August 2015 initially determined intermediate break locations may be used unless redesign of the piping resulting in a change in pipe parameters (diameter, wall thickness, routing) is necessary, or the dynamic effects from the new (as-built) intermediate break locations are not mitigated by the original pipe-whip restraints and jet shields. (3) Breaks in seismically analyzed non-ASME Class piping are postulated according to the same criteria as for ASME Class 2 and 3 piping above.6 (4) The following is applicable to (1), (2), and (3) of this section: If a structure separates a high-energy line from an essential component, that separating structure should be designed to withstand the consequences of the pipe break in the high-energy line that produces the greatest effect at the structure, irrespective of the fact that the criteria identified in 2.A(iii) might not need such a break location to be postulated. (5) Safety-related equipment should be environmentally qualified in accordance with SRP Section 3.11. Appropriate pipe ruptures and leakage cracks (whichever controls) should be included in the design bases for environmental qualification of electrical and mechanical equipment both inside and outside the containment. (iv) The designer should identify each piping run it considered in order to postulate the break locations pursuant to 2.A(iii) above. In complex systems such as those containing arrangements of headers and parallel piping running between headers, the designer should identify and include all such piping within a designated run in order to postulate the number of breaks pursuant to these criteria. (v) With the exceptions of those portions of piping identified in 2.A(ii), leakage cracks should be postulated as follows: (1) For ASME Code, Section III, Class 1 piping, at axial locations where the calculated