Summary

This amendment provides support for the full range of time types specified in ISO 8601:2004 by the introduction of a generic type called TIME and a number of useful and defined time types that are derived from it (and are subsets of it). A subtype notation is specified that can be used to define additional time types, and that enables designers to produce variations of those types suited to their particular applications (for example, restrictions on the values used to represent midnight). The useful time types are DATE (specified using year, month, day), TIME-OF-DAY (specified using hours, minutes, seconds, to various accuracies), DATE-TIME (specified by a combination of a DATE and a TIME-OF-DAY) and DURATION (specified in any combination of time units). The defined time types include types that can be used to specify dates and times (in various forms), time intervals, and recurring time intervals. This amendment specifies the type notation, the subtype notation, the basic value notation, and the XML value notation for these types. It also contains a tutorial annex on the ISO 8601 concepts used in the definition of these types.