Document: NUREG-0800
Document ID: 71224475-ca63-4c09-acc1-c682d58112dd
Document Type: srp
Title: Revision 5 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550082.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
ies and instrumentation uncertainties. However, Regulatory Guide 1.97 identifies that, for a limited number of functionally significant variables (e.g., containment pressure, primary system pressure), instrument ranges should extend beyond values that the selected variables can attain under limiting conditions. Guidance on uncertainties is provided in SRP BTP 7-12. The ranges and footnotes for radiation and meteorological instrumentation that are provided in Revision 3 of Regulatory Guide 1.97 should be applicable for plants using Revision 4 of Regulatory Guide 1.97. Applicants/licensees using Revision 4 should document differences from the Revision 3 ranges and footnotes for radiation and meteorological instrumentation. Minimizing Measurements To the extent practicable, the same instruments should be used for accident monitoring as are used for normal operations of the plant. In cases in which a single display may indicate the reading of more than one instrument, the intent of this recommendation is met if the same variable and same display are used for accident monitoring even though the sensor(s) providing the signal are different. Alternate Instrumentation The use of alternate instrumentation to monitor variables different from those identified in Regulatory Guide 1.97, Revisions 2 and 3, is acceptable, provided that all three of the following criteria are met: a. The alternate instrumentation fulfills the purpose of the variables identified in Regulatory Guide 1.97. b. The alternate instrumentation conforms to the design and qualification criteria for the variables identified in Regulatory Guide 1.97. c. No credit is taken by the applicant/licensee in post-accident procedures, emergency operating procedures, or functional recovery guidelines for indication of the variables identified in Regulatory Guide 1.97 for which the alternative instrumentation is proposed. Revision 4 of Regulatory Guide 1.97 does not identify specific variables to be displayed; therefore,