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What the Thermophysical Property Community Should Know About Temperature Scales



Allan H. Harvey


Temperature scales have evolved through many decades to more accurately represent the thermodynamic temperature. This creates challenges for those who study thermophysical properties, because the temperatures used for literature data may not correspond to the latest international scale. The resulting differences are small, but not necessarily negligible, especially for reference-quality work. Here, we describe the temperature scales that might be encountered in the literature and give guidance for converting them to the International Temperature Scale of 1990 (ITS-90). We pay special attention to the liquid-helium scales used for cryogenic work, where a potentially confusing number of different scales has been used. Advice is given for avoiding common mistakes in dealing with temperature scales in the context of thermophysical property data, including the responsibility of experimentalists to fully document their reported temperatures and the responsibility of modelers to document their handling of any temperature-scale issues.
International Journal of Thermophysics


ITS-90, temperature, temperature scales, thermophysical properties


Harvey, A. (2021), What the Thermophysical Property Community Should Know About Temperature Scales, International Journal of Thermophysics, [online],, (Accessed February 21, 2024)
Created September 3, 2021, Updated November 29, 2022