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The Advanced Dimensional Measurement Systems (ADMS) project provides the measurement science and infrastructure needed by industry to adopt new dimensional
Electricity meters today face unprecedented challenges, from distorted waveforms on the grid, bidirectional metering for renewables, and the use of meters as
Radiometric and photometric measurements require defining apertures. The accuracy to which these measurements can be accomplished requires minimization of the
The Alpha-Gamma device is a totally-absorbing neutron detector that has been used to measure the absolute neutron fluence of a cold, monoenergetic neutron beam
Measurements of radium isotopes in the naturally-occurring radioactive decay chains (i.e., 235U, 238U, and 232Th) are exceedingly important for various
The construction of a new primary calibration facility for air kerma measurements has been completed. It delivers a collimated 137Cs gamma-ray beam in which
The high-dose dosimetry program supports radiation-processing applications by assuring that the absorbed dose to the product, often prescribed or limited by
NIST is in its eighth decade of providing critically evaluated, comprehensive databases of cross-section information for ionizing photons (x and gamma rays)
The fundamental photon and charged particle interaction data and the radiation transport methods, pioneered and developed at NIST to calculate the penetration
NIST provides calibration services for force-measuring instruments by applying known forces, compression, tension or both, to the elastic transducer and
Three dosimetry calibration laboratories accredited by the American Association of Physicists in Medicine (AAPM) routinely perform calibrations of a large
The Dosimetry Group maintains and disseminates the national measurement standards for air-kerma (exposure) from 137Cs and 60Co gamma-ray beams and for absorbed
NIST calibrates certain user-owned encapsulated beta-particle sources and certain standards laboratory transfer instruments for applications in radiation
Small radioactive "seed" sources used in prostate brachytherapy, containing the radionuclides 103Pd, 125I, or 131Cs, are calibrated in terms of air-kerma
The Dosimetry Group calibrates well-type ionization chambers using Xoft miniature x-ray sources, which provide low-energy x-rays (< 50 keV) for electronic
The new NIST x-ray calibration facility has been designed to improve the measurement conditions for x-ray scatter, motion control, environmental conditions
Precise calibration of short-lived radioactive material is essential for nuclear medicine and power plant applications. To deliver such calibrations on-demand
NIST provides the national reference for the calibration of neutron radiation detectors used for personnel protection and for neutron personnel dosimeters.
The neutron source calibration facility operated by NIST is a world-class calibration laboratory providing neutron source calibration services for radioisotopic
Absorbed dose is the energy imparted per unit mass by radiation to an irradiated target. The SI unit of absorbed dose is the gray (abbreviated Gy), equivalent
We are developing instrumentation, standards artifacts, and measurement protocols to characterize appearance attributes including color, texture, and gloss
An international measurement comparison for a 99Tc solution hosted by National Physical Laboratory (NPL) of the UK, (CCRI(II)K-2. 99Tc comparison) was completed
Comparisons for the national standards of air kerma from therapy level and radiation protection gamma-ray beams were conducted by the NIST and the Bureau