This database contains the ITS-90 (International Temperature Scale of 1990) fixed temperature points (exactly 17) and recommended secondary reference temperature points (about 500) along with uncertainties and a comprehensive set of references. In addition, to the recommended values, it contains a large set of individual determinations. This database (as in the prior version) also provides the different thermocouple tables for thermocouples for use on the ITS-90 temperature scale." This database dates to 1995 as a PC version and then ported to an online database in 2000. The database originally simply reproduced the print NIST Monograph 175 [1] and just provide the different thermocouple tables (EMF voltage vs temperature) for Type B, E, J, K, N, R, S, and T thermocouples for use on the ITS-90 temperature scale.[2]
We have significantly enhanced the database. We have added the ITS-90 primary fixed temperature points from Preston-Thomas (1990),[1] the secondary reference temperature points from Bedford et al (1984[3] and Bedford et al. (1996),[4] Crovini, Bedford, and Moser (1977),[5] and the metal (carbide)-carbon transition points from Burgess (2024)[6], the latter provides potential primary fixed points and secondary reference points above the freezing point of copper (the highest fixed point on the ITS-90).
We provide uncertainties to the ITS-90 reference points (T90) and the differences with the thermodynamic temperatures (T) from Gaiser et al (2022),[7] the Consultative Committee for Thermometry,[8] Fischer et al (2011),[9], and Rusby et al (1991).[10] We also provide uncertainties to the secondary reference temperature points.
The Preston-Thomas (1990) ITS-90 paper does not provide references, so we provide many of the relevant references. We also provide references relevant to the secondary reference temperature points given in Bedford et al (1984), Bedford et al. (1996), and Crovini, Bedford, and Moser (1977). We not only provide references for the recommended values, but for values from other sources as well.
We plan to continue this work to update the database with more reported values (especially more recent) from the literature for each primary and secondary temperature points.
[1]. Burns, G. W.; Scroger, M. G.; Strouse, G. F.; Croarkin, M. C.; Guthrie, W. F.; "Temperature-Electromotive Force Reference Functions and Tables for the Letter-Designated Thermocouple Types Based on the ITS-90," NIST Monograph 175, 1993.DOI:
[2]. Preston-Thomass, H.; "The International Temperature Scale of 1990 (ITS-90)," Metrologia 27, 3-10 (1990). DOI:.
[3]. R.E. Bedford, Bonnier, H. Maas, F. Pavese, "Recommended Values of Temperature for a Selected Set of Secondary Reference Points," Metrologia 20, 145-155 (1984). DOI:.
[4]. R. E. Bedford, G. Bonnier, H. Maas, F. Pavese; “Recommended Values of Temperature on the International Temperature Scale of 1990 for a Selected Set of Secondary Reference Points,” Metrologia 33, 133-154 (1996). DOI:.
[5]. L. Crovini, H. J. Jung, R. C. Kemp, S. K. Ling, B. W. Mangum, and H. Sakurai, "The Platinum Resistance Thermometer Range of the International Temperature Scale of 1990," Metrologia 28, 317-325 (1991). DOI:.
[6]. D. R. Burgess, Jr.; “Binary Metal-Carbon Phase-Transition Temperatures,” NIST Technical Note 2278, NIST, Gaithersburg, MD (2024). DOI:.
[7]. C. Gaiser et al., "2022 Update for the Differences Between Thermodynamic Temperature and ITS-90 Below 335 K," J. Phys. Chem. Ref. Data 51, 043105 (2022). DOI:
[8]. Consultative Committee for Thermometry (CCT), "Updated Estimates of the Differences between Thermodynamic Temperature T and the ITS-90 Temperature Scale" BIPM, Sevres, France, 2022.
[9]. J. Fischer, M. de Podesta, K. D. Hill, M. Moldover, L. Pitre, R. Rusby, P. Steur, O. Tamura, R. White, and L. Wolber, "Present Estimates of the Differences Between Thermodynamic Temperatures and the ITS-90," Int. J. Thermophys. 32, 12-25 (2011). DOI:
[10]. R. L. Rusby, R. P. Hudson, M. Durieux, J. F. Schooley, P. P. M. Steur, and C. A. Swenson, "Thermodynamic Basis of the ITS-90," Metrologia 28, 9-18 (1991). DOI: