Document: NUREG-0800
Document ID: c6dbe9ec-b58d-4a77-85ee-47b58571c3c0
Document Type: srp
Title: Revision 6 - August 2016
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1601/ML16019A200.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
s between trip setpoint, allowable value, analytical limit, LSSS, and safety limit. The following additional definitions are provided for reviewer guidance: A. Acceptable as-found band: It is the band around the nominal trip setpoint or previous as-left setting of the instrument within which the as-found setpoint is expected to fall. The band accounts for the uncertainties associated with factors such as instrument reference accuracy, measurement and test equipment (MT&E), readability, normal environment effect, and drift of the instrument components that are being tested, and it accounts only for the duration between the tests. The width of the band is established by the deviation limit (DL), which may be asymmetrical relative to the reference value (nominal setpoint (NSP) or previous as-left) and defines the deviation (from the previous as-left value or NSP) that is expected to occur during the test. It should be noted that the DL must not include the setting tolerance (ST). B. As-left tolerance band or acceptable as-left band: It is the band around the nominal trip setpoint (LSP) - or around any value which is more conservative than the LSP - within which the as-left setpoint must fall at the conclusion of a channel test. The band accounts for the as-left tolerance, which some licensees define as leeway given to the instrument technician or calibration tolerance or setting tolerance. Setting tolerance can be based upon particular uncertainties such as reference accuracy, MT&E, and readability, but the total loop uncertainty analysis must explicitly account for each of these uncertainty terms whether or not the ST incorporates these uncertainties. ST may also be a specified value selected on the basis of engineering judgment or other consideration. However, in that situation, the as-found value must be compared with the previous as-left value. BTP 7-12-5 Revision 6 – August 2016 4. Purpose The purpose of this BTP is to provide guidance for the NRC staff to