This is understood to be the total number of hours worked by the employed personnel during the year.

These hours include:
- Number of hours worked, normal timetable and overtime.
- The duration, in the workplace, of dead time due to occasional lack of work.
- The time corresponding to short rest breaks in the workplace.

The following are not included in hours worked:
- Time which is paid but not worked, such as annual paid holidays, paid public holidays, or sick leave.
- Meal breaks.