Document: NUREG-0800
Document ID: c6f58bab-ddce-42eb-a3ef-02dd3da952fc
Document Type: srp
Title: Revision 3 – December 2016
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1608/ML16085A315.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3
CFR Part: 
CFR Title: 

Content:
pecified in B.1.a of BTP 3-3, “Protection Against Postulated Piping Failures in Fluid Systems Outside Containment,” a review of the piping layout and plant arrangement drawings should clearly show that the effects of postulated piping breaks at any location are isolated or are physically remote from essential systems and components.1 At the designer’s option, break locations as determined from 2A(iii) of this BTP may be assumed for this purpose. (ii) Fluid System Piping in Containment Penetration Areas. Breaks and cracks need not be postulated in those portions of piping from containment wall to and including the inboard or outboard isolation valves, provided that they meet the design criteria of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code), Section III, Subarticle NE-1120, and the following additional design criteria: (1) The following design stress and fatigue limits should not be exceeded: 1 Essential systems and components are those necessary to shut down the reactor and mitigate the consequences of a postulated pipe rupture without offsite power. BTP 3-4-3 Revision 3 –December 2016 For ASME Code, Section III, Class 1 Piping (a) The maximum stress range between any two load sets (including the zero load set) should not exceed 2.4Sm and should be calculated 2 by Eq. (10) in ASME Code, Section III, NB-3653. If the calculated maximum stress range of Eq. (10) exceeds 2.4Sm, the stress ranges calculated by both Eq. (12) and Eq. (13) in Paragraph ASME Code, Section III, NB-3653 should meet the limit of 2.4Sm. (b) The cumulative usage factor (CUF) should be less than 0.1. For new reactor design certification reviews, the staff has considered a CUF limit of 0.4 to be acceptable when the effects of environmental assisted fatigue (EAF) are considered in the piping design. (c) The maximum stress, as calculated by Eq. (9) in ASME Code, Section III, NB-3652 under the loadings resulting from a postulated piping failure