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Metrological Traceability Frequently Asked Questions and NIST Policy



Sally Bruce, Antonio Possolo, Robert Watters


The NIST policy on metrological traceability (NIST P 5800.00, which became effective on May 31st, 2019) is transcribed and supplemented with a review of relevant terminology and with a list of frequently asked questions and answers. This list updates and amplifies a similar list originally prepared by a team organized and led by Richard Kayser, which was published in the World Wide Web, and comprises questions about: metrological traceability in general; establishing metrological traceability; NIST and NIST's role in metrological traceability; NIST products and services; and international aspects of traceability.
Technical Note (NIST TN) - 2156
Report Number


accreditation, calibration, categorical, fitness for purpose, measurand, measurement, nominal, ordinal, qualitative property, quantitative property, reference material, standard reference data, standard reference instrument, standard reference material, traceability chain


Bruce, S. , Possolo, A. and Watters, R. (2021), Metrological Traceability Frequently Asked Questions and NIST Policy, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed June 16, 2024)


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Created May 6, 2021, Updated November 29, 2022