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About PML

The Physical Measurement Laboratory (PML) ( view PML brochure) develops and disseminates the national standards of:

  • length, mass, force and shock, acceleration,
  • time and frequency,
  • electricity, temperature, humidity,
  • pressure and vacuum,
  • liquid and gas flow, and
  • electromagnetic, optical, microwave, acoustic, ultrasonic, and ionizing radiation.

PML's activities range from fundamental measurement research through provision of measurement services, standards, and data. PML applies its measurement capabilities to problems of national significance through collaborations with:

  • industry,
  • universities,
  • professional and standards setting organizations,
  • and other agencies of government.

PML supports the research community in such areas as:  communication, defense, electronics, energy, environment, health, lighting, manufacturing, microelectronics, radiation, remote sensing, space, and transportation.

PML establishes spectroscopic methods and standards for infrared, visible, ultraviolet, x-ray, and gamma-ray radiation; investigates the structure and dynamics of atoms, molecules, and biomolecules; develops the electrical, thermal, dimensional, mechanical, and physical metrology for measuring the properties of precision measurement devices and exploratory semiconductor, quantum electronic, nanoelectronic, bioelectronic, biooptical, optoelectronic, and quantum information devices and systems; and examines the thermophysical and interfacial properties of streams of flowing fluids, fluid mixtures, and solids.

It develops and disseminates national standards by means of calibrations, measurement quality assurance, standard reference materials, technology transfer, education/training, and a comprehensive weights and measurement program to promote uniformity and accuracy at the international, federal, state, and local levels.

It generates, evaluates, and compiles atomic, molecular, optical, ionizing radiation, electronic, and electromagnetic data in response to national needs; measures and improves accuracy of the fundamental physical constants; and develops and operates major radiation sources for measurement science and metrology.

PML is participating in the American Physical Society - Inclusion, Diversity, and Equity Alliance.


General Information: 301-975-4200 (phone); 301-975-3038 (Fax); 100 Bureau Drive, M/S 8400, Gaithersburg, MD 20899-8400

Created February 5, 2009, Updated October 23, 2020