Document: NUREG-0800
Document ID: 2dffe24e-cd37-4ffc-9c37-16faf25676b1
Document Type: srp
Title: Appendix 7-A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500579.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
and systems over their anticipated ranges for normal operations, for anticipated operational occurrences, and for accident conditions as appropriate to ensure adequate safety. Digital instrumentation must respond quickly enough so that the behavior of variables can be ascertained by operators. 10 CFR 50 Appendix A, GDC 19, "Control Room," requires in part that applicants establish a control room from which actions can be taken to operate the nuclear power unit safely under normal conditions, and to maintain the nuclear power unit in a safe condition during an accident. In addition, a remote shutdown capability is required to permit the reactor to be safely shut down. 10 CFR 50 Appendix A, GDC 20, "Protection System Functions," requires in part that the reactor protection system provide automatic initiation so that fuel design limits are not exceeded and so that accidents are sensed and mitigated. Both of these goals require timely operation of protection system components, thus establishing the timing requirements for detecting parameters exceeding their setpoints, and equipment actuation in the protection system. Rev. 4 — June 1997 Appendix 7-A BTP HICB-21-2 10 CFR 50 Appendix A, GDC 21, "Protection System Reliability and Testability," requires in part the high functional reliability of safety systems. Timely operation is necessary for high functional reliability of safety systems. 10 CFR 50 Appendix A, GDC 23, "Protection System Failure Modes," requires in part the protection system to be designed so that if it fails, it fails into a safe state given the anticipated failure modes and conditions in which the failure occurs. This is a design architectural issue aimed at staying within timing limits. 10 CFR 50 Appendix A, GDC 25, "Protection System Requirements for Reactivity Control Malfunctions," requires, in part, reactivity control to prevent fuel design limits from being exceeded. This requires timely operation of the protection features of the reactivity