Federal law caps a commercial driver at 11 hours of driving inside a 14 hour window, after 10 consecutive hours off duty, with a 30 minute break required before the eighth hour of driving. Weekly limits cap total on-duty time at 60 hours in 7 days or 70 in 8.
Those limits exist because fatigue kills, and the industry has known it for a century.
When a driver falls asleep, the question is almost never whether they were tired. It is whether the company’s schedule made that outcome predictable, and the electronic record usually answers it.
The rules, in plain terms
These are the federal limits for property-carrying commercial drivers under 49 CFR Part 395.
| Rule | Limit |
|---|---|
| Driving time | 11 hours maximum |
| Duty window | 14 consecutive hours, after which no driving regardless of breaks |
| Off-duty reset | 10 consecutive hours before the window restarts |
| Break | 30 minutes required before driving beyond 8 cumulative hours |
| Weekly | 60 hours in 7 days, or 70 in 8 for carriers operating every day |
| Restart | 34 consecutive hours off duty resets the weekly count |
The 14 hour window is the one people misunderstand. It runs continuously from the moment the driver goes on duty. Loading delays, traffic, and waiting at a dock all consume it even though no driving is happening. A driver who spends four hours waiting to unload has four fewer hours of usable window, and the load is still due at the same time.
That pressure is where fatigue cases actually start.
Electronic logs changed what can be proven
Paper logbooks were easy to falsify, and the industry called them comic books for a reason. Most commercial vehicles now run electronic logging devices that record duty status automatically from the engine.
An ELD captures engine hours, vehicle movement, miles driven, location at intervals, duty status changes, and the identity of the driver logged in. It also records edits, and who made them.
That last item matters more than anything else on the list. When a carrier’s back office edits a driver’s log, the system keeps a record of the original entry, the change, and who made it. A pattern of edits that move driving time into off-duty status is one of the more damaging things that can appear in a trucking file.
Records are retained under federal rules for a limited period, which is why the preservation demand has to go out in days rather than weeks.
Fatigue is not just the driver’s problem
This is the part that turns a simple negligence claim into a case against the company.
A driver who exceeded the limits broke a rule. The more consequential question is why, and the answers usually point upward:
Dispatch and scheduling. Delivery windows that cannot be met inside legal driving hours. Assignments issued back to back without adequate rest. Dispatch messages pressing a driver who has reported being tired.
Pay structure. Compensation per mile rather than per hour means waiting is unpaid. A driver who loses four hours at a dock has a direct financial incentive to make it up on the road.
Detention time. Shippers and receivers who hold drivers for hours push the entire schedule into the window’s edges. That can reach the shipper as a defendant.
Log falsification culture. Edits, unassigned driving time, and personal conveyance status misused to mask driving.
Hiring and retention. A carrier that hired a driver with a documented fatigue or violation history, or kept one after repeated violations, faces direct negligence claims independent of what happened that day.
Sleep apnea screening. Untreated obstructive sleep apnea is a recognized fatigue risk in commercial driving, and medical certification requirements interact with it.
Those are claims against the carrier for its own conduct, not merely for the driver’s. They survive even where the carrier admits the driver was its employee, and they frequently reach conduct a jury finds far more troubling than a single lapse.
The records that decide it
- ELD data for the trip and the preceding weeks, including the edit history
- Driver qualification file, including prior violations and employment history
- Dispatch communications, messages, and load assignments
- Bills of lading and delivery windows, which show what was demanded
- Detention records at pickup and delivery
- Payroll records, which reveal the incentive structure
- Prior hours-of-service violations across the fleet
- Medical certification and any sleep apnea screening
- The engine control module, for speed, braking, and throttle in the final seconds
- Post-accident drug and alcohol testing, which has a strict time window
Much of this is available only through discovery. None of it is available if it has already cycled out. See who owns the truck that hit you for what you can pull publicly on day one.
What fatigue looks like in the physical evidence
Fatigue crashes have a signature, and reconstruction can often identify it.
No braking. A driver who fell asleep does not brake. The absence of skid marks, and electronic control module data showing no brake application before impact, is powerful.
No evasive steering. Departure from the lane in a straight line rather than a correction.
Time of day. Circadian low points, roughly two to six in the morning and mid-afternoon, are overrepresented.
Road type. Long, monotonous stretches. The rural corridors across West Texas and the long hauls on I-10 and I-20 are exactly the environment where this happens, and they are also where the impact speeds are highest.
What this means for you
If a commercial driver fell asleep and hit your family, three things matter in the first week.
Do not accept an early resolution. Fatigue cases frequently involve carrier conduct that has not surfaced yet, and the value of the case can change substantially once the logs are produced.
Get preservation demands out naming the ELD data, the edit history, dispatch communications, and the driver qualification file specifically. A general request will not produce an edit audit trail.
Understand that the carrier’s investigator is already working. They were at the scene the day it happened. See the rapid response team was there in two hours.
Robert Law Group handles Houston truck accident cases and catastrophic trucking litigation across Texas and Utah, including the long-corridor crashes where fatigue and scheduling pressure are usually the real story. Call 832-509-2303.
Frequently asked questions
How many hours can a truck driver legally drive?
Federal rules allow up to 11 hours of driving within a 14 consecutive hour duty window, following 10 consecutive hours off duty, with a 30 minute break required before driving beyond 8 cumulative hours.
What is an electronic logging device and why does it matter?
An ELD automatically records duty status from the engine, including driving time, movement, and location. It also records edits to the log and who made them, which can reveal falsification.
Can the trucking company be sued if the driver fell asleep?
Yes. Beyond responsibility for the driver’s conduct, a carrier can face direct claims for dispatch and scheduling practices, pay structures that discourage rest, negligent hiring or retention, and failure to enforce hours-of-service compliance.
How do you prove a truck driver fell asleep?
Through the absence of braking or evasive steering in the electronic control module data and physical evidence, combined with hours-of-service records, dispatch communications, and the timing of the crash.
How long are truck driver logs kept?
Electronic logging records are retained under federal rules for a limited period, which is why a preservation demand needs to be sent within days of a crash.