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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.

To see current opportunities at the Office of Weights and Measures for continuing education and training, click here  Resources for Continuing Education and Training.

OWM collaborates with state weights and measures programs, industry, and national standards development organizations and associations in the development of U.S. standards in the form of uniform laws, regulations, and methods of practice.  OWM serves as the U.S. representative to the International Organization of Legal Metrology (OIML) to bring efficiency and cost savings to U.S. manufacturers and other stakeholders doing business overseas, through the promotion of harmonized international standards and regulatory practices.

OWM ensures traceability of state weights and measures standards to the SI; develops procedures for legal metrology inspections and tests; and conducts training for laboratory metrologists and weights and measures officials. OWM provides guidance on model weights and measures laws and regulations adopted by state and local weights and measures programs.  OWM collaborates and works with the National Conference on Weights and Measures (NCWM) in both the development of new, and the revisions to existing, model laws and regulations; and OWM coordinates the development and publication of key NCWM documents.

It is estimated that sales of products or services impacted by weights and measures laws in the United States represent approximately 50 percent of the U.S. Gross Domestic Product. Industry sectors potentially affected by legal metrology standards include retail food sales, other retail sales, petroleum products, transportation, and chemicals.

The NIST Office of Weights and Measures analyzes weights and measures training needs; obtains input from the weights and measures community on legal metrology standards and practices; and designs and delivers training for laboratory metrologists and weights and measures officials.


5786 Fundamentals of Metrology

Mon, Jan 31 - Fri, Feb 4 2022
The 5-day Fundamentals of Metrology seminar introduces participants to the concepts of measurement systems, units

5787 Volume Metrology Seminar

Mon, Feb 7 - Fri, Feb 11 2022
The 5-day OWM Volume Metrology Seminar is designed to enable metrologists to apply fundamental measurement concepts to

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

News and Updates

Making Sure that Lumber Measures Up

For some, it is a shocking revelation. But most Americans eventually come to accept the fact that a “two by four” board is actually 1.5 inches by 3.5 inches (38



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