# Council Directive of 20 December 1979 on the approximation of the laws of the Member States relating to units of measurement and on the repeal of Directive 71/354/EEC (80/181/EEC), Division 1.1.1: Special name and symbol of the SI derived unit of temperature for expressing Celsius temperature

Extent: E+W+S+N.I.

Quantity
Unit
Name
Symbol
Celsius temperature
degree Celsius
°C
Celsius temperature t is defined as the difference t = T – T 0 between the two thermodynamic temperatures T and T 0 where T 0 = 273,15 K. An interval or difference of temperature may be expressed either in kelvins or in degrees Celsius. The unit ‘ degree Celsius ’ is equal to the unit ‘ kelvin ’ .

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Source: https://www.legislation.gov.uk/eudr/1980/181/annex/chapter/I/division/1/division/1.1/division/1.1.1 (the official version)
Page: https://openlegislation.uk/eu-directive-1980-181/annex/chapter-I/division-1/division-1.1/division-1.1.1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.