The ITS-90 extends upwards from 0.65 K to the highest temperature practicably measurable in terms of the Planck radiation law using monochromatic radiation. The ITS-90 comprises a number of ranges and sub-ranges throughout each of which temperatures T90 are defined.

For the International Temperature Scale of 1990, ITS-90, such an accompanying document was prepared in 1990 by Working Group 1 Defining fixed points and interpolating instruments of the CCT and approved by the CCT. It is now called Guide to the Realization of the ITS-90 and posted on the BIPM website.

The International Temperature Scale of 1990 (ITS-90) defines both International Kelvin Temperatures, symbol T 90, and International Celsius Temperatures, symbol t 90. The relation between T 90 and t 90, is the same as that between T and t, i.e.: t90 / °C = T90/K - 273.15 . (2)

2018年5月15日 · ITS-90 contains 17 reference points based on naturally occurring, highly reproducible states: phase transitions (freezing or melting) or the triple points in many familiar, naturally occurring substances.

1990年8月1日 · Mangum, B. and Furukawa, G. (1990), Guidelines for Realizing the International Temperature Scale of 1990 (ITS-90), Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=905199 (Accessed January 26, 2025)

Temperature Scale of 1990 (ITS-90) The ITS-90 extends upwards from 0.65 K to the highest temperature practicably measurable in terms of the Planck radiation law using monochromatic radiation. The ITS-90 comprises a number of ranges and sub-ranges throughout each of which temperatures T90 are defined. Several of these ranges

Definition of the International Temperature Scale of 1990. Between 0.65 K and 5.0 K T 90 is defined in terms of the vapour-pressure temperature relations of 3 He and 4 He.

The International Temperature Scale of 1990 (ITS-90) is a globally recognized temperature scale introduced by the International Committee for Weights and Measures (CIPM). It serves as a global standard for precise temperature measurements and …

Supplementary Information and Differences from Earlier Scales & Appendix. The apparatus, methods and procedures that will serve to realize the ITS-90 are given in "Supplementary Information for the ITS-90".

The ITS-90 specifies a set of fixed points (melting, freezing, triple, or boiling points of various pure substances, see Guide Chapter 2 Fixed points), which are used for the calibration of SPRTs in eleven temperature sub-ranges within the overall range from 13.8033 K to 1234.93 K.