It really depends on your job and position. In IT software, it could be 8-10 hours depending upon the day, the project, etc. I've had some months were it is strictly 8 hours for long stretches.
At least 12, sometimes more.
Answered - Maintenance Mechanic (Current Employee) - San Bernardino, CA
8-9 hours per day. On call 24-7 but rarely called on off times.
Answered - Facilities Coordinator/Property Manager (Former Employee) - Tampa, FL
8 plus if necessary
Answered - Maintenance Technician (Current Employee) - Alexandria, VA