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Resolution 7 of the 9th CGPM (1948)
Version française
Writing and printing of unit symbols and of numbers*

    Principles

    Roman (upright) type, in general lower case, is used for symbols of units; if, however, the symbols are derived from proper names, capital roman type is used. These symbols are not followed by a full stop.

    In numbers, the comma (French practice) or the dot (British practice) is used only to separate the integral part of numbers from the decimal part. Numbers may be divided in groups of three in order to facilitate reading; neither dots nor commas are ever inserted in the spaces between groups.

      Unit Symbol Unit Symbol

      ·metre

      m

      ampere

      A

      ·square metre

      m2

      volt

      V

      ·cubic metre

      m3

      watt

      W

      ·micron

      µ

      ohm

      capital omega

      ·litre

      l

      coulomb

      C

      ·gram

      g

      farad

      F

      ·tonne

      t

      henry

      H

      second

      s

      hertz

      Hz

      erg

      erg

      poise

      P

      dyne

      dyn

      newton

      N

      degree Celsius

      °C

      ·candela

       
         

      (new candela)

      cd

      ·degree absolute

      °K

      lux

      lx

      calorie

      cal

      lumen

      lm

      bar

      bar

      stilb

      sb

      hour

      h

         

    Notes

    1. The symbols whose unit names are preceded by dots are those which had already been adopted by a decision of the CIPM.
    2. The symbol for the stere, the unit of volume for firewood, shall be "st" and not "s", which had been previously assigned to it by the CIPM.
    3. To indicate a temperature interval or difference, rather than a temperature, the word "degree" in full, or the abbreviation "deg" must be used.


Reference:
Comptes Rendus de la 9e CGPM (1948), 1949, p.70

Note:

The CGPM abrogated certain decisions on units and terminology, in particular: micron, degree absolute, and the terms "degree", and "deg", 13th CGPM, 1967 (Resolutions 7 and 3), and the litre; 16th CGPM, 1979 (Resolution 6).

The reader should note that the official version of this Resolution is the French text.

 
Other Resolutions of the 9th CGPM (1948)
Resolution 1
Resolution 2
Resolution 3
Resolution 4
Resolution 5
Resolution 6
Resolution 7
Resolution 8
Resolution 9
Resolution 10