IEC 80000-13

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.

The standard has 14 parts.

ISO 80000-4:2006 supersedes ISO 31-3. and specifies names and symbols for quantities and units of classical mechanics, and defines these names and symbols. The document is under review.

ISO 80000-5:2007 supersedes ISO 31-4 which "gives names, symbols and definitions for quantities and units of thermodynamics". The document is under review.

IEC 80000-6:2008 supersedes ISO 31-5 as well as IEC 60027-1, and specifies names and symbols for quantities and units related to electromagnetism, and defines these quantities and units.

ISO 80000-7:2008 supersedes ISO 31-6, and specifies names and symbols to quantities and units for light and other electromagnetic radiation, and defines these quantities and units. The document is under review.

ISO 80000-8:2007 specifies names, symbols for quantities and units of acoustics and provides definitions for these quantities and units. It supersedes ISO 31-7 and is under review. It has a foreword; introduction; scope; normative references; and names, symbols and definitions. The standard includes definitions of sound pressure, sound power and sound exposure, and their corresponding levels: sound pressure level, sound power level and sound exposure level. For example:

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