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Weights and Measures

To promote uniformity in national and international legal metrology laws, regulations, standards, test procedures, and enforcement practices so as to ensure traceability of measurements to the SI and to enhance consumer protection, foster fair competition, and facilitate economic growth and trade.

OWM fulfills its mission through the following broad activities:

  • Standards development (national and international)
  • Design and development of test and operational procedures
  • Design and delivery of training, in the areas of:
    • laboratory metrology,
    • weights and measures laws and regulations, and
    • weights and measures inspections;
  • Technical guidance
  • Implementation of national policy to establish the SI as the preferred system of weights and measures
  • Publications and outreach


5710 Basic Uncertainty Concepts

Thu, May 20 2021, 2:00 - 4:00pm EDT
This 2-hour webinar provides a very basic introduction to uncertainty calculations and reporting using the 8-step

5711 Volume Metrology Seminar - CANCELED

Mon, Jun 7 2021, 8:00am - Fri, Jun 11 2021, 5:30pm EDT
The NIST Gaithersburg campus is currently in Phase 1 of reopening and is closed to visitors. Do not make any travel

Industry Impacts

Fare Standards for Rideshare Services

To calculate fares, app-based ride services such as Lyft and Uber don’t use traditional taxi meters, but instead combine data from GPS and cellular networks to



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