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Temperature measurements

Radiation thermometers and blackbody sources

Calibration using standard blackbody radiation sources

NPL offer calibration of radiation thermometers, blackbody sources, and tympanic (ear) thermometers by comparison to our standard blackbody radiation sources.

Radiation thermometry is a vital technique in industry offering non-intrusive temperature measurement with a rapid response time for process control. It may be used for measuring temperatures in situations where traditional contact thermometry may be inappropriate or impractical, for example when an object is very hot, moving, in a hostile environment or where contamination must be avoided. Calibrations are performed by comparison to NPL’s standard blackbody radiation sources which operate between -40 °C and +3000 °C.

In order to provide traceability to the ITS-90, NPL maintains a suite of standard blackbody radiation sources which are used for the calibration and evaluation of:

  • infrared radiation thermometers and radiometers 
  • secondary blackbody reference sources 
  • thermal imagers 
  • tympanic ear thermometers 
  • disappearing filament pyrometers

The UKAS (ISO 17025) accredited CMCs for radiation thermometers range from 0.1 °C to 0.3 °C over the temperature range from -40 °C to 1000 °C and from 0.5 °C to 1.5 °C at high temperatures (1000 °C to 3000 °C). Those for secondary blackbody reference sources are slightly higher at the lower temperatures.

Customer blackbody sources may be evaluated by comparison with an NPL standard source using either an infrared radiometer or a suite of transfer standard radiation thermometers operating at wavelengths from 0.65 µm to 14 μm. We can also evaluate the emissivity of a blackbody source by calculation and modelling.

These services are UKAS (ISO 17025) accredited. Peripheral apparatus (such as a suitable furnace) for the operation of the equipment can also be provided.

Don’t see what you are looking for? Our diverse skill set enables us to provide bespoke solutions. Please contact us to discuss your requirements.

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