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The National Conference on Weights and Measures (NCWM) was first held as the “First Annual Meeting of Sealers of Weights and Measures of the United States” in 1905 and as part of the National Bureau of Standards (NBS; now NIST). The NCWM separated its operations from NIST and became a not-for-profit weights and measures association in 1998.

No. The NCWM is a 501(c)(6) not-for-profit corporation and NIST is a non-regulatory federal agency within the Department of Commerce. However, both NCWM and NIST work closely together and share the mutual goal and responsibility of developing the standards in the NIST Handbooks (44, 130, and 133) and facilitating uniformity in weights and measures laws, regulations, standards, and practices in the U.S.

Learn more about the history of the NIST Handbooks and NCWM here.

Staff from NIST OWM serve on each NCWM committee as both members and technical advisors. These “NIST Technical Advisors” provide technical analysis and guidance of all proposals and can also raise new proposals for consideration. They provide expert advice throughout the consensus-based process to assist NCWM in reaching technically-sound decisions in the standards development process.

These are a series of documentary standards that serve as “model” laws, regulations, and procedures to be adopted as legal requirements by federal, state, and local regulatory agencies. They are used to regulate and ensure equity for consumers and sellers in commercial transactions based on weight and measure.

Learn more about the history of the NIST Handbooks and NCWM here.

The NCWM is the principal standards development organization used to develop the “model” laws, regulations, and procedures within NIST Handbooks 44, 130, and 133. NIST is an active member of the NCWM (albeit a non-voting member) and actively participates in the standards development process. However, the standards within NIST Handbooks 44, 130, and 133 reflect what is adopted by the NCWM each year.

Learn more about the history of the NIST Handbooks and NCWM here.

No. NIST does not decide what standards to include in NIST Handbooks 44, 130, and 133. Specific only to these three NIST Handbooks, new standards are proposed to the NCWM and developed via a committee-based consensus process involving NCWM members with technical advice from staff in the NIST Office of Weights and Measures (OWM).

A proposal for a new standard is sufficiently developed through the regional weights and measures associations. Then, it is submitted to the appropriate committee of the NCWM and further developed with the participation of all its members (both voting and non-voting). Voting members include the regulators for each state and territory. Non-voting members include NIST, and representatives from industry, other governmental agencies, and other private organizations. The new standard is then voted on at the NCWM Annual Meeting in July of each year. If adopted by consensus, NIST publishes Handbooks 44, 130, and 133 with those new standards that are approved the following year.

NIST OWM publishes and maintains these standards and provides electronic copies free of charge for NIST Handbooks 44, 130, and 133 (among others) via our website.  We provide the documents in both *.pdf and *.docx formats.  

NCWM members receive a complimentary copy of the NIST Handbooks with their membership.

NIST OWM will provide a printed copy of the requested NIST Handbooks 44, 130,  and 133, but this is subject to availability. You may request a copy at OWM [at] (owm[at]nist[dot]gov).

Created May 11, 2023, Updated May 10, 2024