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Flow Measurement Proficiency Testing



G E. Mattingly


To eliminate measurement-base trade barriers to international commerce, Key Comparisons (KCS) are now being planned in the newly formed Working Group for Fluid Flow (WGFF) in the CIPM to quantify the equivalency of the flow standards maintained in the world's National Measurement Institutes (NMIs). This equivalency will establish the horizontal comparability of flow standards across NMIs. To validate the accuracies of flow calibration laboratories, flow traceability can and should be established and maintained to the flow standards maintained in the country's NMI. This vertical traceability quantifies the validity of flow measurement capabilities within the country's metrological pyramid with the NMI at the peak of the pyramid. The purpose of this paper is to describe flow measurement proficiency testing techniques and their potential for comprising the highly precise KCs needed to quantify the equivalency of flow standards among NMIs as well as for disseminating flow measurement traceability from the country's NMI. Examples are given of recent proficienty testing programs that involved NIST for specific fluids and flow conditions. These demonstrate the unique levels of precision that can be attained with appropriate choices of test conditions, transfer standards, test protocols, and data analysis. Conclusions are drawn that when proficiency tests have been used both to quantify the horizontal comparability I.e., the equivalency of flow standards among the world's NMIs and the vertical traceability to establish traceability to the countrys NMI, a comprehensive heirarchy in flow measurement will be established. In it, the uncertainties quoted for flow measurements will be quantified, verified, understood, and therefore assured for all involved.
Flow Measurement, Practical Guides for Measurement and Control
Ed. 2
Publisher Info
Instrument Society of America, Research Triangle Park, NC


flow measurement, key comparison, proficiency testing, traceability, uncertainty, Youden analysis


Mattingly, G. (2001), Flow Measurement Proficiency Testing, Instrument Society of America, Research Triangle Park, NC (Accessed April 19, 2024)
Created April 1, 2001, Updated June 2, 2021