Document: NUREG-0800
Document ID: 65f2433f-2c4a-4580-b173-0c6da7fa4d73
Document Type: srp
Title: Draft Revision 7 – August 2015
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159A996.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
ocumented basis that justifies taking no action. BTP 7-19-13 Draft Revision 7 – August 2015 (3) When a failure of a common element or signal source shared by the control system and RTS is postulated and the CCF results in a plant response for which the safety analysis credits reactor trip but the failure also impairs the trip function, then diverse means that are not subject to or failed by the postulated failure should be provided to perform the RTS function. The diverse means should assure that the plant response calculated using realistic assumptions and analyses does not result in radiation release exceeding 10 percent of the applicable siting dose guideline values or violation of the integrity of the primary coolant pressure boundary. (4) When a CCF results in a plant response for which the safety analysis credits ESF actuation and also impairs the ESF function, then a diverse means not subject to or failed by the postulated failure should be provided to perform the ESF function. The diverse means should assure that the plant response calculated using realistic assumptions and analyses does not result in radiation release exceeding 10 percent of the applicable siting dose guideline values or violation of the integrity of the primary coolant pressure boundary. (5) No failure of monitoring or display systems should influence the functioning of the RTS or ESF. If a plant monitoring system failure induces operators to attempt to operate the plant outside safety limits or in violation of the limiting conditions of operation, the analysis should demonstrate that such operator-induced transients will be compensated by protection system function. (6) For safety systems to satisfy IEEE Std 603-1991 Clauses 6.2 and 7.2, a safety- related means shall be provided in the control room to implement manual initiation of the automatically initiated protective actions at the system level or division level (depending on the design) of the RTS and ESF functions. This