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Physical Measurement Laboratory

PML is a world leader in the science of measurement. We determine the definitive methods for nearly every kind of measurement employed in commerce and research, provide NIST-traceable calibrations, and disseminate standards and best practices throughout the nation. At the same time, PML works continuously at the outermost frontiers of metrology, devising tools and techniques to meet the ever-changing demands of American industry and science.

SI Redefinition

Outer circle has one wedge for each of the 7 SI units (kilogram, meter, second, ampere, kelvin, mole, and candela) and the inner circle has wedges for the 7 important constants.
Credit: BIPM

NIST is producing a series of special reports on the worldwide consensus plan to redefine four of the seven basic units of measurement in the International System of Units in terms of invariants of nature.

Explore these stories, as they become available, on the SI Redefinition Portal.

News and Updates

Events

NIST Spectroradiometry Short Course

Tue, Apr 7 - Fri, Apr 10 2020
NIST is closely monitoring guidance from Federal, State, and local health authorities on the outbreak of COVID-19. To

5620: Volume Metrology Seminar

Mon, Apr 20 - Fri, Apr 24 2020
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

Nanolithography Design Tools

Accurate production of nanoscale features on semiconductor chips is essential to their performance, but typical design tools cater to the dominance of straight

High-Power Lasers for Manufacturing 

Measuring the intensity of high-power lasers used by manufacturers for precision cutting and welding can be difficult due to large instrumentation challenges

Brain Mapping Technologies

Magnetic signals produced by electrical currents in the brain can be used to map brain processes and help in the diagnosis and treatment of disease

Awards

2019 PECASE - Alexey Gorshkov

The Presidential Early Career Award for Scientists and Engineers (PECASE) is the highest honor bestowed by the United States Government to...

2019 PECASE - Franklyn Quinlan

The Presidential Early Career Award for Scientists and Engineers (PECASE) is the highest honor bestowed by the United States Government to...

2019 PECASE - Laura Sinclair

The Presidential Early Career Award for Scientists and Engineers (PECASE) is the highest honor bestowed by the United States Government to...

Press Coverage

A more perfect unit: the new mole

Popular Science
A video about the redefinition of the mole, featuring NIST's Savelas Rabb, Robert Vocke, and Stephan Schlamminger.

Contacts

PML Director and PML Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretaries to Director Kushmerick and Deputy Director Williams