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International Legal Metrology Program

The primary mission of the International Legal Metrology Program (ILMP) is to facilitate U.S. participation in the technical work of the International Organization of Legal Metrology (OIML)

About the International Legal Metrology Program

The International Legal Metrology Program (ILMP) is part of the Office of Weights and Measures within NIST's Physical Measurements Laboratory.

What is Legal Metrology?

Legal Metrology is the practice and process of applying regulatory structure and enforcement to metrology.

What We Do

The primary mission of the International Legal Metrology Program (ILMP) is to facilitate U.S. participation in the technical work of the International Organization of Legal Metrology (OIML), a treaty organization that develops voluntary standards (called Recommendations) intended to be used to harmonize national legislation among Member States in areas where regulated instruments and measurements are involved. The Group coordinates participation of U.S. manufacturers, users of weighing and measuring instruments, legal metrology officials and other U.S. stakeholders in the technical work of OIML by circulating draft Recommendations and other OIML publications for comment, and by leading U.S. delegations to OIML Technical Meetings. By authority of the U.S. State Department, the Group votes on OIML technical matters, including at the level of the International Committee of Legal Metrology (CIML), which is the technical and administrative oversight body of OIML. The Group also maintains liaisons with several national, regional, and international organizations, and actively participates in two Regional Legal Metrology Organizations (RLMOs), the Asia Pacific Legal Metrology Forum (APLMF) and the Inter-American Metrology System (SIM).

Our Work

The International Legal Metrology Group coordinates U.S. participation in the:


5802 Fundamentals of Metrology

Mon, Aug 22 - Fri, Aug 26 2022
The 5 day Fundamentals of Metrology seminar is an intensive course that introduces participants to the concepts of

5812 Volume Metrology Seminar

Mon, Aug 29 - Fri, Sep 2 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



General Information: