ISO 31 (Quantities and units, International Organization for Standardization, 1992) is a superseded international standard concerning physical quantities, units of measurement, their interrelationships and their presentation. It was revised and replaced by ISO/IEC 80000.

Parts

The standard comes in 14 parts:

A second international standard on quantities and units was IEC 60027. The ISO 31 and IEC 60027 Standards were revised by the two standardization organizations in collaboration (, ) to integrate both standards into a joint standard ISO/IEC 80000 - Quantities and Units in which the quantities and equations used with SI are to be referred as the International System of Quantities (ISQ). ISO/IEC 80000 supersedes both ISO 31 and part of IEC 60027.

Coined words

ISO 31-0 introduced several new words into the English language that are direct spelling-calques from the French. Some of these words have been used in scientific literature.

New phraseExisting phraseTechnical meaning
massic <quantity>specific <quantity>a quantity divided by its associated mass
volumic <quantity>[volumic] <quantity> densitya quantity divided by its associated volume
areic <quantity>surface <quantity> densitya quantity divided by its associated area
lineic <quantity>linear <quantity> densitya quantity divided by its associated length

Related national standards

  • Canada: CAN/CSA-Z234-1-89 Canadian Metric Practice Guide (covers some aspects of ISO 31-0, but is not a comprehensive list of physical quantities comparable to ISO 31)
  • United States: There are several national SI guidance documents, such as , , , IEEE/ASTM SI 10, SAE J916. These cover many aspects of the ISO 31-0 standard, but lack the comprehensive list of quantities and units defined in the remaining parts of ISO 31.

See also

  • SI – the international system of units
  • BIPM – publishes freely available information on SI units , which overlaps with some of the material covered in ISO 31-0
  • IUPAP – much of the material in ISO 31 comes originally from Document IUPAP-25 of the Commission for Symbols, Units and Nomenclature (SUN Commission) of the International Union of Pure and Applied Physics
  • IUPAC – some of the material in ISO 31 originates from the Interdivisional Committee on Terminology, Nomenclature and Symbols of the International Union of Pure and Applied Chemistry
  • Quantities, Units and Symbols in Physical Chemistry – this IUPAC "Green Book" covers many ISO 31 definitions
  • IEC 60027 Letter symbols to be used in electrical technology
  • ISO 1000 SI Units and Recommendations for the use of their multiples and of certain other units (bundled with ISO 31 as the ISO Standards Handbook – Quantities and units)

Notes

External links

  • – Quantities, units, symbols, conversion factors