Document: NUREG-0800
Document ID: 2349ea77-1f6e-45e4-a2df-f56249a774f1
Document Type: srp
Title: CONTROL ROD DRIVE SYSTEMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070364.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.4
CFR Part: 
CFR Title: 

Content:
on and safety is augmented by the capability of the CRDS to perform its safety function under earthquake conditions. 3. GDC 14 establishes requirements regarding the RCPB portion of the CRDS. The CRDM is relied upon, in part, to provide a barrier to the release of fission products to the containment through proper design of the control rod drive housing and components that are part of the RCPB. Application of the GDC 14 criteria to the CRDM components functioning as a RCPB increases safety by ensuring that the RCPB will have an extremely low probability of failure. 4. GDC 26 establishes requirements regarding the reactivity control systems redundancy and capability. The CRDS is one of the reactivity control systems relied upon during normal operating and anticipated operational occurrences to control reactivity changes to 3.9.4-7 DRAFT Rev. 3 - April 1996 ensure that the fuel design limits are not exceeded. Application of GDC 26 criteria to the CRDS improves safety by providing protection for the fuel matrix and cladding, the primary barrier to the release of fission products. 5. GDC 27 establishes requirements regarding the combined reactivity control system capability. The CRDS is one of the reactivity control systems relied upon during postulated accident conditions to control reactivity changes to ensure that the capability to cool the core is maintained. Requiring compliance with GDC 27 for the CRDS augments the protection provided for the primary fission product barrier by providing one means to ensure that the core, under postulated accident conditions, will be maintained in a coolable geometry. 6. GDC 29 establishes requirements regarding the capability of the CRDS to accomplish its safety functions in the event of anticipated operational occurrences. In order to provide protection for the fuel matrix and cladding, the primary barrier to the release of fission products, the CRDS must have a high probability of accomplishing its safety function during