Document: NRC Regulatory Guide
Document ID: 96ecfd93-e64a-4f35-93fe-d3b95daac61d
Document Type: regulatory_guide
Title: Monitoring the Effectiveness of Maintenance at Nuclear Power Plants + HISTORY –HISTORY 06/2018 – DG-1336 , Proposed Revision 4 09/2011 – DG-1278 , Proposed Revision 3 08/1996 – DG-1051 , Proposed Revision 2 06/1994 – DG-1031, Proposed Revision 1 11/1992 – DG-1020, Proposed Revision 0 (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1812/ML18129A080.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.160
CFR Part: 
CFR Title: 

Content:
th (e.g. FLEX) equipment could prevent safety-related structures, systems, and components from fulfilling their safety-related function; or could cause a reactor scram or actuation of a safety-related system. Sections 8.2.1.4 “Nonsafety-Related SSCs Whose Failure Prevents Safety- Related SSCs From Fulfilling Their Safety-Related Function” and 8.2.1.5 “Nonsafety-Related SSCs Whose Failure Causes A Reactor Scram or Actuates Safety Systems” address those topics. Section 8.2.1.3 “Nonsafety-Related SSCs that are used in Emergency Operating Procedures” is endorsed with the following clarification. 10 CFR 50.65(b)(2)(i) requires in part that the scope of the monitoring program includes nonsafety related SSCs that “are used in plant emergency operating procedures (EOPs);” Section 8.2.1.3 defines “Mitigate or Mitigating” as “actions or steps taken to lessen the severity or the adverse consequences of the event/symptom that necessitated entry into the EOP.” While it is true that utilizing the FSG could lessen the severity or the adverse consequences of the initiating event or symptom that led into the EOPs, the FSGs are not required to mitigate the within-design-basis accidents addressed by the EOPs; the FSGs are not essential to or relied upon for the successful mitigation. Therefore, FSG equipment used to address a beyond-design-basis event condition is not required to perform the EOP mitigating function and is not “used in plant emergency operating procedures” for that purpose under 10 CFR 50.65(b)(2)(i). Accordingly, it’s not scoped into the Maintenance rule under the “used in [EOPs]” part of 50.65(b)(2)(i). However, for uses different than described above, where FSG equipment is “relied upon to mitigate accidents or transients,” addressed by the EOPs, then the equipment would scope in under the “relied upon” part 50.65(b)(2)(i) as discussed in Section 8.2.1.2 of NUMARC 93-01.. Section 9.4.2 “Monitoring” is endorsed with the