Document: NUREG-0800
Document ID: b09bdecd-fb52-4a15-ab35-7b597cbbaa13
Document Type: srp
Title: Appendix 7-A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500546.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
be feasible or prudent to achieve the range of Appendix 7-A Rev. 4 — June 1997 BTP HICB-13-3 isothermal conditions in the RCS for in-situ verification of the complete calibration range of the RTDs. Nevertheless, the applicant/licensee should provide assurance that the calibration and response time for each RTD has not significantly changed due to aging or degradation of the sensor and its installation. One method acceptable to the Staff is to periodically provide an installed reference RTD that has been recently calibrated and response-time tested. The remaining "similar" RTDs may be cross-correlated to the reference RTD to identify any significant degradation in performance. The "similar" RTDs are those which can be shown to be subject to sufficiently similar temperature and flow conditions in the RCS. While this method does not provide for complete calibration verification of each RTD over its range, the Staff has found the method adequate for timely detection of drift or degradation of RTDs, provided that the guidance herein is applied. This guidance addresses the following topics: • Traceability of the installed reference RTD to laboratory calibration data. • Acceptable methods for in-situ testing of RTDs. • Response time testing. • "As-found" and "as-left" surveillance data. • Control/protection interaction or common-mode failure during in-situ testing. 2. Information to be Reviewed The information to be reviewed consists of specifications, drawings, and analyses of the proposed RTD cross-calibration program. 3. Acceptance Criteria Supporting Analysis Analyses, and information on the instrument maintenance and calibration program should be provided to support the adequacy of the cross-calibration program. The analysis should, as a minimum, address the following topics. • Justification that the cross-calibration program is consistent with the characteristics of the RTD sensors, including RTD specifications, range, accuracy, repeatability, dynamic