Ukas Temperature Calibration

By Author: Jen Smith
Total Articles: 17
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What is UKAS?
UKAS (United Kingdom Accreditation Service) is the sole body recognised by HM Government for assessing and accrediting the competence of calibration and testing laboratories.

UKAS Accreditation, ISO/IEC17025 and ISO9001
Laboratories are accredited by UKAS to ISO/IEC 17025: 2005 which is the internationally recognised standard for the competence of calibration and testing laboratories.

The systems, people, their training, and technical capabilities of a UKAS accredited laboratory are regularly and thoroughly examined and tested by UKAS auditors, each of them specialists in their field. It is an expensive and time consuming process, but our ongoing accreditation and fulfilment of the requirements of ISO17025 means you can rest assured that we have the competence, impartiality and performance capability necessary to consistently deliver technically valid calibration results each and every time.

A UKAS temperature laboratory uses a range of reference platinum resistance thermometers, noble metal thermocouples, stirred liquid baths, specially designed isothermal calibration furnaces ...
... and black body sources to provide a comprehensive facility for cost effective thermometer calibration over the range -35ºC to 1,200ºC.

Both contact thermometers such as thermocouples, prts and dial thermometers; and non-contact infrared thermometers and thermal imaging cameras are covered. We can even calibrate temperature sources such a dry block calibrators or calibration baths.

The temperature calibration service company will also be able to offer stand alone UKAS calibration of digital thermometer readouts. As these are essentially an electrical instrument they are calibrated in the calibration services electrical laboratory.

The calibration uncertainties detailed below are typical examples of our best calibration and measurement capability for a reasonably repeatable thermometer. The final uncertainties quoted on the calibration certificate will include an allowance for the actual repeatability of the thermometer under test during the calibration. If the thermometer was submitted with its own readout and hence calibrated as a system, then an additional allowance will be included in the uncertainty budget to cover the resolution of the thermometer readout.

Indicating Thermometer Calibration (thermometer with readout, calibrated as a system). The device under test may be an electronic display with an attached probe. All thermometer probe types are covered, including PRT, thermistor or thermocouple. Dial thermometer and chart recorder type devices are also covered. The basic calibration uncertainty will be a little better than the uncertainties achievable for 4 wire PRTs, plus allowances for repeatability of the device under test and resolution of its readout.

Calibration of Infrared Thermal Imaging Camera (Thermal Imager)
Thermal imaging cameras that are able to display a measured radiant temperature should be calibrated. Our temperature ranges and uncertainties for UKAS calibration of a thermal imager will be similar to those quoted for an infrared thermometer temperature calibration.