Document: NUREG-0800
Document ID: a20ea81d-33c2-4a0c-a3b4-216d45d6fccd
Document Type: srp
Title: FEEDWATER SYSTEM PIPE.BREAKS INSIDE AND OUTSIDE CONTAINMENT (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350148.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.2.8
CFR Part: 
CFR Title: 

Content:
ic objective of the review of feedwater system pipe break events is to confirm that the reactor primary system is maintained in a safe status for a range of feedwater line breaks up to and including a break equivalent in area to the double-ended rupture of the largest feedwater line. RSB acceptance criteria are based on meeting the relevant requirements of the following regulations: A. General Design Criteria 27 and 28, as they relate to the reactor coolant system being designed with appropriate margin to assure that acceptable fuel design limits are not exceeded, and that the capability to cool the core is maintained. B. General Design Criterion 31, as it relates to the reactor coolant system being designed with sufficient margin to assure that the boundary behaves in a nonbrittle manner and that the probability of propagating fracture is minimized. C. General Design Criterion 35, as it relates to the reactor cooling system and associated auxiliaries being designed to provide abundant emergency core cooling. D. 10 CFR Part 100, as it relates to the calculated doses at the site boundary. In addition, task action plan items that are necessary to meet the requirements to maintain adequate decay heat removal and reactor coolant pump integrity and operation are items II.E.1, II.K.2.1, II.E.1.2, II.K.2.8, II.K.3.5, II.K.2.16, II.K.3.25, and II.K,3.40 of NUREG-0718 and NUREG-0737 (Refs. 6 and 7). Specific criteria necessary to meet the relevant requirements of these regula- tions are as follows: 1. Pressure in the reactor coolant and main steam systems should be main- tained below 110% of the design pressures (Ref. 3) for low probability events and below 120% of the design pressures for very low probability events such as double-ended guillotine breaks. 2. The potential for core damage is evaluated on the basis that it is acceptable if the minimum DNBR remains above the 95/95 DNBR limit for PWRs based on acceptable correlations (see SRP Section 4.4). If the DNBR falls