Document: NUREG-0800
Document ID: d5452e7b-1e61-498b-9e3d-71073b3328ef
Document Type: srp
Title: LEAK-BEFORE-BREAK EVALUATION PROCEDURES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0302/ML030280295.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.3
CFR Part: 
CFR Title: 

Content:
c effects of postulated pipe ruptures may be eliminated when leak before-break technology is shown to be applicable. Requirements for con tainment design, emergency core cooling system performance and environmental cualification of electrical and mechanical equipment are not affected. (See the supplementary information to the final broad scope GDC-4 amendment which permits an exception to this statement for equipment qualification under certain conditions). Applicants for operating licenses seeking to modify design features to take advantage of ledk-before-break technology are required to reflect the revised design in an amendment to the pending FSAR. If the design change modifies design criteria set forth in the PSAR, an amendment to the applicable con struction permit may also be necessary. After leak-before-break technology results are accepted for specific piping systems at specific plants, any proposed future plant modifications in operat ing conditions or plant features may require an assessment of the impacts on the original conclusions from the initial leak-before-break evaluation. When leak-before-break is successfully demonstrated, all postulated pipe ruptures are eliminated in the specific piping system under review. Ruptures in branch connections to the piping system under review are still postulated, unless these lines also qualify for leak-before-break. An evaluation of dynamic effects at these branch connections is required, as for example, in heavy component support design or redesign. When dynamic effects of pipe rupture are eliminated from the design basis, current NRC criteria and industry codes, such as the ASME Code, may be required for calculating the seismic loads in the heavy component support redesign of operating plants or plants under construction (for example, when snubbers are reduced in number or capacity in older operating plants; on the other hand, changing high strength fastener material would not require the use of current codes or