ISO 4031 [SEP] standards body
ISO 4031
ISO 4031 is an international standard first issued in 1978 by the International Organization for Standardization. It defined the representation of local time differentials, commonly referred to as time zones. It has since been superseded by a newer standard, ISO 8601. This newer standard sets out the current formats for local time differentials and so ISO 4031 is no longer in use.
"Z") that are given specific meanings within the standard; the implication is that some commonplace ways of writing parts of dates, such as "January" or "Thursday", are not allowed in interchange representations.
History.
The first edition of the ISO 8601 standard was published as "ISO 8601:1988" in 1988. It unified and replaced a number of older ISO standards on various aspects of date and time notation: ISO 2014, ISO 2015, ISO 2711, ISO 3307, and ISO 4031