NIST has also established a NIST U.S. National Work Group (USNWG) on Field Reference Meters through which this work is being accomplished. This USNWG provides a forum for the development of uniform and appropriate legal metrology standards that harmonize, where possible, with related national and international standards. As of June 2022, the USNWG includes 51 members representing 11 states and 7 industry organizations in addition to NIST and Measurement Canada. Membership in the USNWG has been inclusive and continues to remain open to any interested party.
The objectives of the USNWG are to:
- investigate the feasibility of using Coriolis-type mass flow meters (indicating in mass, volume, and/or other units) as field test standards in the inspection and testing of commercial liquid/gas measuring systems, including an investigation of and comparisons with current methodologies and standards (e.g., gravimetric testing and neck-type volumetric field test standards and associated test procedures);
- promote, encourage, and participate in the establishment of a comprehensive set of standards, test procedures, and associated methodologies for the use of this type of device as a field test standard;
- develop and document the methodology and process used (including procedures, forms, and other tools) to validate a given design(s) of Coriolis-type mass flow meter for use as a field test standard to enable that methodology and process to be used to validate other designs of Coriolis-type mass flow meters as well as other metering technologies;
- facilitate measurements that establish metrological traceability to the International System of Units (SI) as specified in the current edition of the International Vocabulary of Metrology (VIM); and
- provide recommendations for consideration and use by weights and measures jurisdictions, other work groups, and others interested in this technical work and its application.
This work will include an assessment of whether or not mass flow meters can meet the criteria established in the Fundamental Considerations of NIST Handbook 44 for use as field test standards in testing commercial measuring systems.