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OWM Programs and Core Areas

As part of NIST’s portfolio of metrology services, the Office of Weights and Measures (OWM) provides legal metrology standards, laboratory and field inspection (i.e., legal devices), standard operating procedures, and weights and measures training. OWM works with a range of stakeholders ranging from industry, consumer groups, State weights and measures program officials and metrologists, Federal agencies, and national and international standards development organizations (SDOs) and associations. Through these partnerships and our NIST programmatic efforts, OWM provides services in the following core areas:

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U.S. and International Standards. OWM develops documentary standards important for legal metrology devices and laboratory metrology in practice. OWM leads U.S. national working groups while representing the U.S. and NIST within international and national SDOs (International Organization of Legal Metrology (OIML) and National Conference on Weights and Measures (NCWM), respectively) to develop new and maintain existing uniform U.S. laws, regulations, and methods of practice to harmonize with international standards and regulatory practices.

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SI Traceability for the States. OWM facilitates traceability of State weights and measures standards to the International System of Units (SI) through NIST; develops procedures for legal metrology inspections and tests; and provides guidance on uniform weights and measures laws and regulations adopted by State and local weights and measures programs. OWM also provides a payment in kind recognition program that includes accreditation (via the National Voluntary Laboratory Accreditation Program (NVLAP)) and proficiency testing opportunities.

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Technical Guidance and Training. Through direct input from the weights and measures community on legal metrology standards and practices, OWM designs and delivers training for State laboratory metrologists, weights and measures officials, legal metrology device practitioners, and metric (SI) educators. To see current opportunities for training and continuing education, see our Calendar of Events.

OWM staff serve as technical advisors and secretariats to SDOs and working groups; investigate new technologies and develop inspection procedures; progress and maintain NIST Handbooks, guidance documents, test and examination operation procedures and other documentary standards; operate the laboratory metrology program to ensure traceability to the SI of State weights and measures standards; and develop and provide in-person, virtual and hybrid training for stakeholders and the U.S. metric and weights and measures communities at-large.

Our diverse group of staff are comprised of weights and measures coordinators, laboratory metrologists, legal metrology and international standards experts, and training and administrative professionals who collaborate across these metrology programs:

A directory of OWM Staff and Technical Experts is provided here.

Created July 8, 2016, Updated April 20, 2022