ISO 31 (

Quantities Quantity or amount is a property that can exist as a multitude or magnitude, which illustrate discontinuity and continuity. Quantities can be compared in terms of "more", "less", or "equal", or by assigning a numerical value multiple of a u ...

and units,

International Organization for Standardization The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. M ...

, 1992) is a superseded international standard concerning

physical quantities A physical quantity (or simply quantity) is a property of a material or system that can be quantified by measurement. A physical quantity can be expressed as a ''value'', which is the algebraic multiplication of a '' numerical value'' and a '' ...

, units of

measurement Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared to ...

, their interrelationships and their presentation. It was revised and replaced by

ISO/IEC 80000 ISO/IEC 80000, ''Quantities and units'', is an international standard describing the International System of Quantities (ISQ). It was developed and promulgated jointly by the International Organization for Standardization (ISO) and the Intern ...

Parts

The standard comes in 14 parts: * ISO 31-0: General principles (replaced by

-1:2009) *

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 It was superseded in 2006 by ISO 80000-3 and again in 2019 by ISO 80000-3:2019. Definitions Its defi ...

Space Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless ...

and

time Time is the continuous progression of existence that occurs in an apparently irreversible process, irreversible succession from the past, through the present, and into the future. It is a component quantity of various measurements used to sequ ...

(replaced by

-3:2007) * ISO 31-2: Periodic and related

phenomena A phenomenon ( phenomena), sometimes spelled phaenomenon, is an observable Event (philosophy), event. The term came into its modern Philosophy, philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be ...

(replaced by

-3:2007) * ISO 31-3: Mechanics (replaced by

-4:2006) *

ISO 31-4 ISO 31-4 is the part of international standard ISO 31 ISO 31 (Physical quantity, Quantities and Physical unit, units, International Organization for Standardization, 1992) is a superseded international standard concerning physical quantities, u ...

Heat In thermodynamics, heat is energy in transfer between a thermodynamic system and its surroundings by such mechanisms as thermal conduction, electromagnetic radiation, and friction, which are microscopic in nature, involving sub-atomic, ato ...

(replaced by

-5) * ISO 31-5:

Electricity Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

and

magnetism Magnetism is the class of physical attributes that occur through a magnetic field, which allows objects to attract or repel each other. Because both electric currents and magnetic moments of elementary particles give rise to a magnetic field, ...

(replaced by

-6) * ISO 31-6:

Light Light, visible light, or visible radiation is electromagnetic radiation that can be visual perception, perceived by the human eye. Visible light spans the visible spectrum and is usually defined as having wavelengths in the range of 400– ...

and related

electromagnetic radiation In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...

s (replaced by

-7) * ISO 31-7:

Acoustics Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician ...

(replaced by

-8:2007) *

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''. Quantities and units Notes In the tables of quantities and their units, the ...

: Physical

chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules a ...

and

molecular physics Molecular physics is the study of the physical properties of molecules and molecular dynamics. The field overlaps significantly with physical chemistry, chemical physics, and quantum chemistry. It is often considered as a sub-field of atomic, mo ...

(replaced by

-9) * ISO 31-9: Atomic and

nuclear physics Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies th ...

(replaced by

-10) * ISO 31-10:

Nuclear reaction In nuclear physics and nuclear chemistry, a nuclear reaction is a process in which two atomic nucleus, nuclei, or a nucleus and an external subatomic particle, collide to produce one or more new nuclides. Thus, a nuclear reaction must cause a t ...

s and

ionizing radiation Ionizing (ionising) radiation, including Radioactive decay, nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionization, ionize atoms or molecules by detaching ...

s (replaced by

-10) *

ISO 31-11 ISO 31-11:1992 was the part of international standard ISO 31 that defines ''mathematical signs and symbols for use in physical sciences and technology''. It was superseded in 2009 by ISO 80000-2:2009 and subsequently revised in 2019 as ISO-80000 ...

: Mathematical signs and

symbol A symbol is a mark, Sign (semiotics), sign, or word that indicates, signifies, or is understood as representing an idea, physical object, object, or wikt:relationship, relationship. Symbols allow people to go beyond what is known or seen by cr ...

s for use in the physical sciences and

technology Technology is the application of Conceptual model, conceptual knowledge to achieve practical goals, especially in a reproducible way. The word ''technology'' can also mean the products resulting from such efforts, including both tangible too ...

(replaced by ISO 80000-2:2009) * ISO 31-12: Characteristic numbers (replaced by

-11) * ISO 31-13:

Solid state physics Solid-state physics is the study of rigid matter, or solids, through methods such as solid-state chemistry, quantum mechanics, crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics. Solid-state p ...

(replaced by

-12) A second international standard on quantities and units was

IEC 60027 IEC 60027 (formerly IEC 27) is a technical standard, technical international standard for letter symbols published by the International Electrotechnical Commission (IEC), comprising the following parts: * IEC 60027-1: General * IEC 60027-2: Telecom ...

. 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, ''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 English is a West Germanic language that developed in early medieval England and has since become a English as a lingua franca, global lingua franca. The namesake of the language is the Angles (tribe), Angles, one of the Germanic peoples th ...

that are direct spelling- calques from the French. Some of these words have been used in scientific literature.

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 a
NIST SP 811NIST SP 330NIST SP 814
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.

Notes

References

* (contains both ISO 31 and ISO 1000) *

External links

ISO TC12 standards
– Quantities, units, symbols, conversion factors {{DEFAULTSORT:Iso 31 #00031 #00031 + Measurement

Parts

Coined words

Related national standards

See also

Notes

References

External links