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Traceable Comparisons of Water-Triple-Point Cells

Published

Author(s)

Weston L. Tew

Abstract

A specific sub-set of comparison data is presented for two NIST water-triple-point cells that provide traceability to the results of the 2023 Consultative Committee for Thermometry CCT-K7.2021 CIPM Key Comparison of Water-Triple-Point Cells. NIST had initially been an official participant in the CCT-K7.2021 but decided to withdraw from the comparison after the breakage of two NIST transfer cells. Despite this status as a withdrawn former participant, enough NIST data was taken prior to the comparison to provide a direct linkage to the results of the K7.1 using the measurements on a NIST transfer cell performed by the Pilot Laboratory, the National Research Council of Canada (NRC). The NIST data was obtained from routine scale maintenance and research activities, and hence did not conform to the official protocol of the CCT-K7.2021, but these data are of good quality and sufficient to establish an overall transfer uncertainty of less than 0.1 mK. The linkage does not convey an official status suitable for establishing Calibration Measurement Capabilities (CMCs) under the Mutual Recognition Arrangement (MRA). However, the linkage is sufficient to provide evidence of traceability to the CCT-K7.2021 and supports NIST Quality System requirements for thermometric standards under the ISO 17025(2017).
Citation
NIST Interagency/Internal Report (NISTIR) - 8533
Report Number
8533

Keywords

Consultative Committee on Thermometry, Fixed Point Cells, International Comparisons, International Temperature Scale, kelvin, Temperature Standards, Water Triple Point.

Citation

Tew, W. (2024), Traceable Comparisons of Water-Triple-Point Cells, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.IR.8533, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=956926 (Accessed December 4, 2024)

Issues

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Created November 8, 2024