Document: NUREG-0800
Document ID: d5a274a9-ea29-4a99-9cbe-73eefa2e90f4
Document Type: srp
Title: REACTOR CORE ISOLATION COOLING SYSTEM (BWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340631.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.6
CFR Part: 
CFR Title: 

Content:
t must maintain the reactor water inventory above the top of the active fuel until the reactor is depressurized sufficiently to permit operation of the low pressure 5.4.6-3 Rev. 3 - April 1984 cooling systems. The RCIC system, in conjunction with the HPCS (or HPCI) system, the safety/relief valves, and the suppression pool cooling mode of the RHR system must be capable of removing fission product decay heat and other residual heat from the reactor core following shutdown so as to preclude fuel damage or reactor coolant pressure boundary overpressuriza- tion. Since RCIC in conjunction with HPCS (or HPCI) is used to provide makeup inventory in some modes of residual heat removal, these systems should jointly meet the guidelines of BTP RSB 5-1, attached to SRP Section 5.4.7. 2. The RCIC system is also used to supply reactor coolant makeup for small leaks. Accordingly, the systems must meet the requirements of General Design Criterion 33 (Ref. 4) in this regard. 3. Historically, credit has been taken for RCIC system capability to mitigate the consequences of certain abnormal events; however, since the cooling function is redundant to the HPCI or HPCS system, the RCIC system itself is not required to meet the single failure- criterion, but in conjunction with HPCS (or HPCI) must satisfy the single failure criterion in this regard. In addition, the RCIC system is to perform its function without the availability of any a-c power per the requirements of General Design Criterion 34 (Ref. 2), and in conjunction with HPCS (or HPCI) must be designed to assure an extremely high probability of accomplishing its safety function as required by General Design Criterion 29 (Ref. 6). 4. As a system which must respond to certain abnormal events, the RCIC system must be designed to seismic Category I standards (discussed in SRP Section 3.2.1) and must not be shared among nuclear power units except as permitted by General Design Criterion 5 (Ref. 7). 5. The RCIC and HPCS (or HPCI)