Truck Crashes Due to Fatigue and Hours of Service Violations

The Current Hours-of-Service Rules Explained

Under 49 CFR Part 395, property-carrying CMV drivers must follow these limits:

The 11-Hour Driving Limit

A driver may drive a maximum of 11 hours after 10 consecutive hours off duty. This is the core driving limitation. Once a driver reaches 11 hours behind the wheel, they must stop driving until they’ve taken another 10-hour off-duty period. This rule exists because FMCSA research shows that crash risk increases substantially as driving hours accumulate.

The 14-Hour On-Duty Window

A driver may not drive beyond the 14th consecutive hour after coming on duty, following 10 consecutive hours off duty. This is a hard limit — once the 14-hour window closes, no driving is permitted regardless of how many hours were actually spent behind the wheel. Loading time, fueling, paperwork, and waiting at docks all count against this window. Off-duty time during the window does not extend it.

The 30-Minute Break Requirement

Drivers must take a break of at least 30 consecutive minutes after 8 cumulative hours of driving. Under the current rule (effective September 29, 2020), this break can be satisfied by any period of 30 consecutive minutes spent not driving — including on-duty not-driving time. Before the 2020 revision, the break had to be off-duty time.

The 60/70-Hour Weekly Limit

A driver may not drive after accumulating 60 hours on duty in 7 consecutive days, or 70 hours on duty in 8 consecutive days. A driver may restart this period after taking 34 or more consecutive hours off duty. This rule prevents cumulative fatigue from building up over a work week.

The Sleeper Berth Provision

Drivers may split their required 10-hour off-duty period, as long as one period is at least 7 consecutive hours in the sleeper berth and the other is at least 2 hours off duty (inside or outside the berth), with both periods totaling at least 10 hours. Neither qualifying period counts against the 14-hour driving window.

The ELD Mandate and Hours-of-Service Enforcement

The FMCSA’s Electronic Logging Device (ELD) mandate requires most CMV drivers to use certified electronic logging devices to record their hours of service — replacing the paper logbooks that were notoriously easy to falsify. ELDs automatically record driving time when the vehicle is in motion, making it harder for drivers and carriers to conceal HOS violations.

Despite the ELD mandate, violations persist. Drivers and carriers use several methods to circumvent the rules:

• Driving under a second ELD profile or “ghost” account
• Editing ELD records after the fact — while edits are logged, patterns of manipulation can be difficult to detect without careful review
• Disconnecting from the ELD during short driving periods
• Using the “unassigned driving time” loophole — driving time that isn’t assigned to any driver’s profile
• Exploiting the short-haul exception to avoid ELD requirements entirely

Why HOS Violations Are So Dangerous

The science behind hours-of-service regulations is clear. Fatigue degrades driving performance in ways that are comparable to alcohol impairment:

• Being awake for 18 hours produces impairment equivalent to a blood alcohol concentration (BAC) of 0.05%
• Being awake for 24 hours is equivalent to a BAC of 0.10% — above the legal limit in every state
• Fatigue reduces reaction time, impairs judgment, and increases the likelihood of lane departures and rear-end collisions
• Microsleep episodes — brief, involuntary periods of unconsciousness lasting 4-5 seconds — can occur without the driver even being aware. At highway speed, that’s 400+ feet of uncontrolled travel.

These risks are multiplied when the vehicle involved is an 80,000-pound tractor-trailer traveling at interstate speeds on corridors like I-65 and I-64 through Kentucky.

Liability in Hours-of-Service Violation Crashes

When a truck crash is caused by a fatigued driver who exceeded HOS limits, liability can extend beyond the driver to include:

• The motor carrier — Carriers are responsible for monitoring their drivers’ compliance with HOS rules. If the carrier knew or should have known the driver was exceeding limits, the carrier is directly liable.
• Dispatchers and fleet managers — If a dispatcher assigned loads that made compliance impossible, or pressured a driver to keep driving, they bear responsibility.
• The parent company — Large carriers operating through subsidiaries or independent contractor arrangements may still bear liability if they controlled the driver’s schedule or operations.