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:
of the position below and of BTP 3-4 are intended to implement this intent with due consideration of the special nature of certain dual purpose systems and the need to define and to limit to a finite number the types and locations of piping failures to be analyzed. Although various measures for the protection of safety-related systems and components are outlined in this position, the preferred method of protection is based upon separation and isolation by plant arrangement. Past applications for CP & Operating Licenses (OL) contained plant layouts where safety-related equipment or structures were located near the main steam and feedwater high energy lines on the basis of utilization of the "break exclusion" design basis in these lines. In consideration of the large magnitude of potential energy stored in these (main steam and feed) systems during normal plant operation, BTP 3-3 is intended to give clear guidance on acceptable methods for protecting essential equipment from the effects of postulated failures in these systems. B. BRANCH TECHNICAL POSITION 1. Plant Arrangement Protection of essential systems and components1 against postulated piping failures in high or moderate energy fluid systems that operate during normal plant conditions and that are located outside of containment, should be provided by items a, b, or c below in order of their preference. a. Plant arrangements should separate fluid system piping from essential systems and components. Separation should be achieved by plant physical layouts that provide sufficient distances between essential systems and components and BTP 3-3-3 Revision 3 - March 2007 fluid system piping such that the environmental effects of any postulated piping failure therein cannot impair the integrity or operability of essential systems and components. The following considerations should also be made: (1) Even though portions of the main steam and feedwater lines meet the break exclusion requirements of item 2.A(ii) of BTP