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Metrology

Mass metrology

News and Updates

NIST Office of Weights and Measures Info Hours

2025 NIST OWM “Info Hours” Series

The NIST Office of Weights and Measures (OWM) is pleased to announce the schedule for the 2025 Info Hours series. An Info Hour is a one-hour session that

Blog Posts

A researcher wearing a lab coat uses tongs to place a silvery sphere into a large scientific device as another researcher looks on.

One of the World’s Roundest Objects Is Helping to Build a Better Mass Measurement

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View from the back of a darkened movie theater shows the heads of the audience and a screen reading: Measurement in the Movies.

Measurement in the Movies

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Title card reads "A Scientific Christmas Tale" with the NIST logo in a wreath and flashing holiday lights.

A Scientific Christmas Tale

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Events

Projects and Programs

OWM Laboratory Metrology Training for mass metrology

OWM Training Program: Metrology, Metrication, and More!

Ongoing
OWM offers a variety of in-person, online, and "blended" training classes and materials that provide guidance instruction on national legal metrology standards, weights and measures field inspection procedures, and laws and regulations related to packaging and labeling. OWM provides technical
DPO sensor

Quantifying the environmental contributions to mass change

Ongoing
Experiments using two types of centimeter scale oscillators are described: the double paddle oscillator (DPO) and a commercial quartz crystal microbalance (QCM). Double Paddle Oscillator (DPO) Since mass changes are mostly on the surface of mass artifacts, we have implemented a micro-weighing sensor
NIST-4

Precision Electro-Mechanical Experiments (PREME)

Ongoing
NIST-4 Kibble Balance Previously called ‘the Electronic Kilogram’ Project, a major component of PREME is the realization of SI unit of mass, the kilogram, using the NIST-4 Kibble balance, the fourth generation of Kibble balances at NIST. This is accomplished through a high-accuracy comparison of

Publications

Thoughts on the Kibble-Robinson Theory

Author(s)
Lorenz Keck, Kumar Arumugam, Leon Chao, Zane Comden, Frank Seifert, David Newell, Darine El Haddad, Stephan Schlamminger
We revisit the Kibble-Robinson Theory (KRT), first proposed in 2014 by Kibble and Robinson, which significantly simplifies the construction and operation of

The Quantum Electro-Mechanical Metrology Suite

Author(s)
Frank Seifert, Lorenz Keck, David B. Newell, Darine El Haddad
The National Institute of Standards and Technology (NIST) is building a robust open-source hardware and software Quantum Electro-Mechanical Metrology Suite

Gravimetric deposition of microliter drops with radiometric confirmation

Author(s)
Denis E. Bergeron, Richard Essex, Svetlana Nour, Gordon A. Shaw, R. Michael Verkouteren, Ryan P. Fitzgerald
A manual gravimetric dispensing technique is demonstrated using a micropipettor modified for use with removeable microcapillaries. Liquid scintillation sources