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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

Sounding Out a New Way to Measure Gas Flow

Researchers at NIST have developed a new — and sound — way to accurately measure the rate at which gas flows in and out of a vessel. The technique, which uses

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

Patents

Contacts

PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretaries