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Taximeters: U.S. National Work Group

The U.S. National Work Group (USNWG) on Taximeters completed a major step in the development of regulatory standards when the work group’s proposed changes to NIST Handbook 44 were adopted by the National Conference on Weights and Measures in July 2017. The changes included a new separate code that applies to systems now being referred to as Transportation Network Measurement Systems (TNMS).

This new tentative Handbook 44 first appeared in the 2018 edition of Handbook 44 and is intended to be used on a trial basis pending that code becoming permanent. The USNWG is anticipating feedback from regulators that will use the tentative TNMS Code during field inspections in an experimental manner to determine if further development of that code is needed prior to it becoming a permanent Handbook 44 code.

The transportation-for-hire industry is evolving rapidly and many of the providers that had used more traditional-type of devices (taximeters) that obtained measurement data from vehicle components are transitioning to the use of location services and software-based meters. The USNWG has been somewhat inactive for a period while the new Handbook 44 standard is undergoing further vetting however, it is clear there will be additional work necessary to complete adequate regulatory coverage considering the emerging technologies incorporated into this service industry.  Details of USNWG on Taximeters meetings may be found in the meeting summaries by clicking on 'Archive Meeting Summaries'.



Created September 24, 2014, Updated March 28, 2022