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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.

News and Updates

Solved: The Mystery of the Cloudy Filters

There’s a mystery happening in some satellites facing the Sun, and scientists from the National Institute of Standards and Technology (NIST) and the Laboratory

Events

5841 Mass Metrology Seminar

Mon, Apr 10 - Fri, Apr 21 2023
The Mass Metrology Seminar is a two-week, "hands-on" seminar. It incorporates approximately 30 percent lectures and 70

Awards

Press Coverage

The Deprecation of the US Survey Foot

The American Surveyor
Some of you know about the deprecation of the U.S. survey foot already, and some may be asking “What the heck is deprecation?” So let’s start with a definition

Patents

Contacts

PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretaries