ISO 31-2 is the part of
international standard
international standard is a technical standard developed by one or more international standards organization, standards organizations. International standards are available for consideration and use worldwide. The most prominent such organization ...
ISO 31
ISO 31 ( Quantities and units, International Organization for Standardization, 1992) is a superseded international standard concerning physical quantities, units of measurement, their interrrelationships and their presentation. It was revised and ...
that defines names and symbols for
quantities and
units related to ''periodic and related phenomena''.
Its definitions include:
Units of time
#00031-2
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