World Metrology Day is an activity of the International Bureau of Weights and Measures, of which the United States is a member. NIST is the U.S. national metrological institute, and NIST's Physical Measurement Laboratory (PML) sets the definitive U.S. standards for nearly every kind of measurement employed in commerce, government operations, and research -- sometimes across more than 20 orders of magnitude.
PML 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. Its activities range from fundamental measurement research through provision of measurement services, standards, and data.
TIME NIST develops and operates the atomic clocks that
set the official U.S. time, and distributes time information
by radio, Internet, and other methods.
DIMENSIONS NIST supports precision measurements
and calibrations ranging from a fraction of a nanometer
to tens of kilometers.
WEIGHT The Office of Weights and Measures helps
ensure the reliability of many different devices used in
commerce, from grocers' scales to gasoline pumps.
MASS/FORCE NIST measures masses as small as a few
millionths of a gram, and measures forces from tens of
piconewtons to a million pounds.
RADIATION NIST maintains and disseminates the
standards or safe use of ionizing radiation in medicine,
industry, and homeland security.
TEMPERATURE The nation relies on NIST research and protocols for temperature control of processes from petroleum management to vaccine storage.
COMMUNICATIONS NIST standards and calibrations
improve the reliability of signal transmission and the
quality of microelectronic components.