Document: NRC Regulatory Guide
Document ID: 30e6fa68-c7c1-4266-ba45-e06d1bbc07a0
Document Type: regulatory_guide
Title: Criteria for Accident Monitoring Instrumentation for Nuclear Power Plants (Rev. 5)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1708/ML17083A134.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.97
CFR Part: 
CFR Title: 

Content:
e associated with plant-specific operating procedures or guidelines). Rather, the scope of the analysis for variables of this type should be as inclusive as possible. Thus contingency variables may or may not be selected as a result of that analysis. 4. The ranges of instrumentation should include appropriate margins, as noted by the following clarifications to Clause 5.1, “Range”: In the second paragraph, the second sentence is clarified as follows: These variables shall have extended ranges, sufficient range to cover, with appropriate margin, the predicted limits of the variables and address a source term that considers a fuel damage. The second paragraph is clarified to include the following: The range of instrumentation used to implement EOPs [emergency operating procedures] should cover, with appropriate margin, the predicted full range of the variables with the consideration of analytical uncertainties and environment measurement errors under design-basis accident conditions. The last paragraph, is clarified to include the following: The instrumentation used to implement SAMGs [severe accident monitoring guidelines] should have sufficient range to cover, with appropriate margin, the predicted limits of the variables. 5. The accuracy of instrumentation should be derived from the licensing basis, and is clarified to include the following to Clause 5.2, “Accuracy”: Instrumentation used to implement EOPs must fulfill accuracy requirements derived from the plant design basis. During SAMG implementation, although the value of a variable may be needed, it is usually more important to follow the trends of the variables used. The accuracy requirements specified for each severe accident mitigation strategy are based on the level of accuracy needed for decision making for support of the mitigation strategy or for support of emergency preparedness functions. If redundant instrumentation is provided, or where spatial orientation and distribution is required for