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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


5826 Fundamentals of Metrology

Mon, Jan 30 - Fri, Feb 3 2023
The 5-day Fundamentals of Metrology seminar is an intensive course that introduces participants to the concepts of

5827 Mass Metrology Seminar

Mon, Feb 6 - Fri, Feb 17 2023
The Mass Metrology Seminar is a two-week, "hands-on" seminar. It incorporates approximately 30 percent lectures and 70


Press Coverage

Research Bits: Dec. 13

Semiconductor Engineering
Engineers at Caltech and the University of Southampton integrated an electronic and photonic chip for high-speed communication in data centers.



NIST Inventors
Sergey Polyakov and Ivan Burenkov
patent description We invented a flow cytometer that can self-calibrate in an absolute way that can reach the sensitivity for quantification and enumeration of a single and small number of biological markers per a biological entity. The cytometer uses a photon-number resolving detector (or a


PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretaries