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 It is superseded by ISO/IEC 80000.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.
ISO 31-0 introduced several new words into the English language that are direct spelling-calques from the French. The intention was that these words be used in scientific papers for the sake of convenience and clarity.
|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|
IEC 60027 (formerly IEC 27) is a technical international standard for letter symbols published by the International Electrotechnical Commission, comprising the following parts:
IEC 60027-1: General
IEC 60027-2: Telecommunications and electronics
IEC 60027-3: Logarithmic and related quantities, and their units
IEC 60027-4: Symbols for quantities to be used for rotating electrical machines
IEC 60027-6: Control technology
IEC 60027-7: Physiological quantities and unitsA closely related international standard on quantities and units is ISO 31. The ISO 31 and IEC 60027 Standards are being revised by the two standardization organizations in collaboration. The revised harmonized standard is known as ISO/IEC 80000, Quantities and units. It supersedes both ISO 31 and part of IEC 60027.ISO/IEC 80000
ISO 80000 or IEC 80000 is an international standard promulgated jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC).
The standard introduces the International System of Quantities (ISQ). It is a style guide for the use of physical quantities and units of measurement, formulas involving them, and their corresponding units, in scientific and educational documents for worldwide use. In most countries, the notations used in mathematics and science textbooks at schools and universities follow closely the guidelines in this standard.The ISO/IEC 80000 family of standards was completed with the publication of Part 1 in November 2009.ISO 31-0
ISO 31-0 is the introductory part of international standard ISO 31 on quantities and units. It provides guidelines for using physical quantities, quantity and unit symbols, and coherent unit systems, especially the SI. It is intended for use in all fields of science and technology and is augmented by more specialized conventions defined in other parts of the ISO 31 standard. ISO 31-0 was withdrawn on 17 November 2009. It is superseded by ISO 80000-1. Other parts of ISO 31 have also been withdrawn and replaced by parts of ISO 80000.ISO 31-1
ISO 31-1 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to space and time. It was superseded in 2006 by ISO 80000-3.ISO 31-12
ISO 31-12 gives name, symbol and definition for 25 selected characteristic numbers used for the description of transport phenomena.
ISO 31-13 gives name, symbol and definition for 62 quantities and units of solid state physics. Where appropriate, conversion factors are also given.ISO 31-4
ISO 31-4 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to heat. It is superseded by ISO 80000-5.
Its definitions include:
Annex A of ISO 31-4 lists units of heat based on the foot, pound and second and some other units, including the degree Rankine, degree Fahrenheit, British thermal unit and others. Annex B lists conversion factors for three versions of the calorie.ISO 31-8
ISO 31-8 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to physical chemistry and molecular physics.ISO 31-9
ISO 31-9 gives name, symbol and definition for 51 quantities and units of atomic and nuclear physics. Where appropriate, conversion factors are also given. Annex A includes names of symbols of the chemical elements, Annex B the notation of symbols for chemical elements and nuclides, Annex C the original names and symbols for nuclides of radioactive series, Annex D examples of relations in different systems of equations using different systems of units.ISO 80000-1
ISO 80000-1:2009 is a standard describing scientific and mathematical quantities and their units. The standard, whose full name is Quantities and units Part 1: General was developed by the International Organization for Standardization (ISO), superseding ISO 31-0. It provides general information concerning quantities and units and their symbols, especially the International System of Quantities and the International System of Units, and defines these quantities and units. It is a part of a group of standards called ISO/IEC 80000.ISO 80000-2
ISO 80000-2:2009 is a standard describing mathematical signs and symbols developed by the International Organization for Standardization (ISO), superseding ISO 31-11. The Standard, whose full name is Quantities and units — Part 2: Mathematical signs and symbols to be used in the natural sciences and technology, is a part of the group of standards called ISO/IEC 80000.ISO 80000-3
ISO 80000-3:2006 is an ISO standard entitled Quantities and units – Part 3: Space and time, superseding ISO 31-1 and ISO 31-2. It is a part of the group of standards called ISO/IEC 80000, which together form the International System of Quantities.
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