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ISO 31 (Quantities and units, International Organization for Standardization, 1992) is a deprecated international standard for the use of physical quantities and units of measurement, and formulas involving them, in scientific and educational documents. It is superseded by ISO/IEC 80000.
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.
|New phrase||Existing phrase||Technical meaning|
|massic <quantity>||specific <quantity>||a quantity divided by its associated mass|
|volumic <quantity>||[volumic] <quantity> density||a quantity divided by its associated volume|
|areic <quantity>||surface <quantity> density||a quantity divided by its associated area|
|lineic <quantity>||linear <quantity> density||a quantity divided by its associated length|