Hours of Service and Fatigue Management
This domain tests the federal hours-of-service limits that apply to passenger-carrying drivers, plus the fatigue judgment questions that come with a load of people depending on you.
Core rules
- 10-hour driving limit: you may not drive after 10 hours of driving that follows 8 consecutive hours off duty.
- 15-hour on-duty window: no driving after the 15th consecutive hour on duty, even if you have driving hours left.
- 60 hours in 7 consecutive days or 70 hours in 8 consecutive days, depending on the carrier's operation.
- 30-minute break after 8 cumulative hours of driving without at least a 30-minute interruption.
- A 34-hour restart resets the 60/70-hour cycle.
- Record your duty status accurately; ELDs are standard, and falsifying a log is a serious violation.
- Fatigue is a hazard: the body's low points fall roughly between 2 and 6 a.m. and again in the mid-afternoon.
- Countermeasures: stop somewhere safe, take a short nap, use caffeine strategically, get out and move, and do not push through micro-sleeps.
Worked example
A driver clocks on at 5 a.m., drives 3 hours, takes a 45-minute break, drives 4 more hours, and wants one final 3-hour leg. Total driving is 10 hours, but the 15-hour window closed at 8 p.m., so the last leg is not legal even though driving hours remain.
Traps that cost marks
Confusing on-duty time with driving time; thinking a break restarts the 15-hour window; assuming the 30-minute break resets the 10-hour limit; logging personal time as off duty when it is not.