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Calibration standards for radiation thermometry are disseminated in the form of radiation thermometers, tungsten strip lamps and blackbodies. These disseminated standards are made traceable to the SI. Continuous effort is made to improve the transfer standards and procedures to lower the total uncertainties. The NIST radiation thermometry scales are periodically compared against other national laboratories in international comparisons sponsored by the Consultative Committee on Thermometry (CCT).


radiation thermometry

Radiation thermometers are calibrated using a range of variable-temperature blackbodies. For heatpipe blackbodies and fluid-stirred blackbodies, the temperatures of these blackbodies are determined using platinum resistance thermometers. These blackbodies can also be assigned temperatures using working standard radiation thermometers. The thermodynamic temperatures of high temperature blackbodies can be determined using detector-based methods.


We offer measurement services for radiance temperature and heat flux sensor calibrations through the NIST Calibration Services.

For technical information about these services, see NIST SP 250-43: Radiance temperature calibrations and NIST SP 250-65: Heat-flux sensor calibration.

To order a calibration, see Calibration Services' Radiance temperature measurements.

Major Accomplishments

Realization of detector-based radiation thermometry.

Created September 17, 2015, Updated June 7, 2023