Non-uniqueness of the ITS-90 (uncertainties in temperature measurements)

Abstract

Causes of uncertainties in temperature measurements are analysed. Some uncertainties are intrinsic to the temperature scale itself (built-in uncertainties). The rest are due to an assortment of experimental uncertainties. A simplified calibration procedure is proposed in the temperature range 0 C ≤ ≤ 660 C that reduces the time (and thus the cost) of calibration by about 30 % without a significant change in the accuracy of the scale imprinted on the calibrated platinum resistance thermometers.