Document: NUREG-0800
Document ID: 243e1ce7-857c-48e4-9eb7-6125311da9be
Document Type: srp
Title: RESIDUAL HEAT REMOVAL (RHR) SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070437.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.7
CFR Part: 
CFR Title: 

Content:
ed in the heat exchangers is transported to the ultimate heat sink by the service water system. Other means of removing decay heat in the event that the RHR system is inoperable have been proposed for some BWRs. These approaches use some of the piping that is used for the steam condensing mode of RCIC. These approaches are also covered by this SRP section. The RHR system in PWRs is utilized to cool the core during shutdown operations, including reduced inventory and mid-loop operations. High RHR system availability and reliability during shutdown conditions is important to mitigating risk and maintaining an appropriate level of safety. The methods used to ensure high reliability of the RHR system under these conditions are reviewed in this SRP section.6 The reactor coolant temperatures and pressure must be decreased before the low pressure RHR system can be placed in operation; therefore, the review of the decay heat removal function must consider all conditions from shutdown at normal reactor operating pressure and temperature to the cold depressurized condition. RSB SRXB reviews the requirements for leakage detection 7 and control reliability and capability of removing decay heat identified in NUREG-0660 8 (II.E.3.2 and II.E.3.3), NUREG-0718 (II.B.7), and NUREG-0737 (Reference 23) item 9 (III.D.1.1). 10 5.4.7-3 DRAFT Rev. 4 - April 1996 Review Interfaces:11 SRXB also performs the following reviews under the SRP sections indicated:12 1. As part of its primary review responsibility for SRP Section 3.12 (proposed), the SRXB reviews the design of the RHR systems for new light-water reactor designs to verify, to the extent practical, that low-pressure portions of the RHR that interface with the RCS will withstand full RCS pressure. If designing the RHR with an ultimate rupture strength capable of withstanding full RCS pressure is not possible, the reviewer verifies that appropriate compensating measures have been taken in accordance with the review provided in SRP