Are there any Timekeeping standards or specifications?

Question

Hi,

I'm currently thinking about a timekeeping application which can store and process information about the times and durations somebody is working.

There is national law about working times (at least in Germany), which should be considered. But what about more technical standards?

Are there any standards or spezification of models or interfaces etc. refering to timekeeping?

Thanks in advance.

Answer 1

ISO 8601, especially Durations and Intervals section.

Answer 2

Coordinated Universal Time?