Document: NUREG-0800
Document ID: c755e557-3a72-423f-92bc-0f0270936e27
Document Type: srp
Title: RESIDUAL HEAT REMOVAL (RHR) SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1006/ML100680577.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.7
CFR Part: 
CFR Title: 

Content:
and jet impingement. The safety function of the RHR system is to transfer heat from the reactor to the environment during and after plant shutdown. To ensure the availability of the decay heat removal function, the RHR system must be capable of performing heat transfer under the expected operational and postulated accident conditions for the plant. These conditions include consideration of the dynamic effects of flow instabilities and the loadings caused by water hammer events. Compliance with GDC 4 enhances plant safety by providing assurance that the dynamic effects of events such as flow instabilities and water hammer will not affect the capability of the RHR system to remove decay heat. 3. GDC 5 prohibits the sharing of SSCs among nuclear power units unless it can be shown that such sharing will not significantly impair the ability of the SSCs to perform their safety functions, including, in the event of an accident in one unit, and orderly shutdown and cooldown of the remaining units. The RHR systems are relied upon to transfer decay heat from the reactor to the environment after a reactor shutdown. The RHR system must be designed such that the ability to perform this and other designated safety-related functions is not compromised for each unit regardless of equipment failures or other events that may occur in another unit. Meeting the requirements of GDC 5 enhances plant safety by providing assurance that the unacceptable effects of equipment failures or other events occurring in one unit of a multiunit site will not prevent an orderly shutdown and cooldown of the unaffected unit(s). 4. GDC 19 requires that a control room be provided from which actions can be taken to operate the nuclear power unit during both normal operating and accident conditions, including the LOCA. BTP 5-4 provides guidance for compliance with GDC 19 with regard to achieving cold shutdown from the control room using only safety-grade equipment. The RHR system is required for safe