Duration is the total length of the training in hours.
For example:
- "2 hours" is entered as: 2 or 2:00
- "1 and a half hours" is entered as: 1.5 or 1:30
- "45 minutes" is entered as: 0.75 or 0:45
- "20 minutes" is entered as: 0:20
If the training occurs over two or more time periods, the duration is the combined total of the time periods.
This field is optional.