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The Redefinition of the SI: Impact on Calibration Services at NIST



Neil M. Zimmerman, Jon R. Pratt, Michael R. Moldover, David B. Newell, Gregory F. Strouse


As most readers are probably at least vaguely aware, it is likely that the SI system of units will be redefied in 2018. This redefinition would fundamentally change the logical structure of the SI, with one result being a substantial change in how mass is disseminated within national measurement institutes (NMI's) such as the National Institute of Standards and Technology (NIST). However, we expect that the only impact on how customers see calibration services will be small step changes that we expect to document and publicize to customers in advance. In this article, we list the main areas of calibration services at NIST, describe how for most of them there will be negligible impact, discuss the impact on mass and DC electrical calibrations, and explain our best guesses as to how we expect to make a seamless transition for customers in those two areas.
Measure: The Journal of Measurement Science


SI redefinition, NIST calibration services


Zimmerman, N. , Pratt, J. , Moldover, M. , Newell, D. and Strouse, G. (2015), The Redefinition of the SI: Impact on Calibration Services at NIST, Measure: The Journal of Measurement Science, [online], (Accessed May 29, 2024)


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Created June 1, 2015, Updated February 19, 2017