Quick answer
Hours of service violations happen when a truck driver drives or works longer than federal limits allow. For property-carrying drivers, the main limits are 11 hours of driving within a 14-hour window after 10 hours off duty, a 30-minute break after 8 hours of driving, and 60 or 70 on-duty hours over 7 or 8 days (49 CFR 395.3). ELD logs, fuel receipts, toll data and dispatch records can help show a violation.
Hours of service violations are a common thread in truck crashes involving driver fatigue. Federal rules limit how long a truck driver may drive and work before resting. When a driver or carrier ignores those limits, a tired driver may end up behind the wheel of a truck that may weigh up to 80,000 pounds, the general federal limit on Interstate highways (23 CFR 658.17 (opens in a new tab)), on a Phoenix freeway. This guide explains the rules, how violations are uncovered, and why acting quickly matters. For the bigger picture, start with our guide to Phoenix truck accident claims.
Why fatigue matters on Phoenix roads
Phoenix is a major stop on long-haul routes. Trucks running I-10 between Los Angeles and Phoenix cross long stretches of desert with few towns, little shade and a steady, monotonous drive. Drivers heading north on I-17 climb toward Flagstaff after a long day. Many reach the Valley near the end of a shift, just as they hit dense traffic at junctions like the Stack or the I-10/Loop 202 interchanges.
Heat adds another layer. Phoenix averages about 111 days a year at or above 100 degrees, based on 1991–2020 data from the National Weather Service (opens in a new tab). Long hours in a hot cab, poor sleep in a sleeper berth and pressure to make delivery windows can all add to fatigue. Hot pavement may also add stress to tires, a topic our guide to jackknife, rollover and tire blowout crashes covers.
If your crash happened on the West Valley stretch of I-10, see our I-10 truck accident guide as well.
The federal hours-of-service rules
The main limits for drivers of property-carrying trucks are in 49 CFR 395.3 (opens in a new tab). Both the driver and the motor carrier are bound by them. The rule says no motor carrier shall "permit or require" a driver to violate them.
| Rule | What it means |
|---|---|
| 10 hours off duty | A driver may not drive without first taking 10 consecutive hours off duty. |
| 14-hour window | A driver may not drive after 14 consecutive hours after coming on duty following 10 hours off. Breaks do not extend this window, except qualifying sleeper berth periods. |
| 11-hour driving limit | A driver may drive a total of 11 hours within that 14-hour window. |
| 30-minute break | A driver may not drive if more than 8 hours of driving time have passed without at least a consecutive 30-minute interruption. Off-duty, sleeper berth or on-duty not-driving time can count. |
| 60/70-hour limit | A driver may not drive after 60 on-duty hours in 7 consecutive days, or 70 hours in 8 consecutive days if the carrier operates every day of the week. |
| 34-hour restart | The 7- or 8-day period may end with the start of an off-duty period of 34 or more consecutive hours. |
Source: 49 CFR 395.3 (opens in a new tab); for sleeper berth periods and the 14-hour window, 49 CFR 395.1(g)(1)(iii)(B) (opens in a new tab).
Other exceptions exist. Short-haul drivers who stay within 150 air miles of their normal work reporting location, are released within 14 hours and meet other conditions do not have to keep logs, though their employer must keep time records for 6 months (49 CFR 395.1(e) (opens in a new tab)). A driver who runs into adverse driving conditions may, in some cases, drive up to two extra hours to finish the run or reach a safe place (49 CFR 395.1(b) (opens in a new tab)).
The sleeper berth rules
Many long-haul trucks have a sleeper berth. A driver may use it to get the required 10 hours off duty in several ways, including 10 consecutive hours in the berth, or a combination of berth and off-duty time (49 CFR 395.1(g) (opens in a new tab)).
A driver may also split the 10 hours into two periods if:
one period is at least 7 consecutive hours in the sleeper berth,
neither period is shorter than 2 consecutive hours,
the two periods add up to at least 10 hours, and
driving time before and after each rest period stays within the 11-hour and 14-hour limits.
When split this way, the qualifying rest periods do not count against the 14-hour window (49 CFR 395.1(g)(1)(ii)–(iii) (opens in a new tab)).
Split sleeper calculations can be confusing, which is one reason logs from long-haul trips deserve careful review.
The fatigue rule
Even a driver within the hour limits may not drive while too fatigued or ill to drive safely. The carrier may not require or permit it either (49 CFR 392.3 (opens in a new tab)).
The ELD mandate
Most motor carriers must install electronic logging devices (ELDs) and require their drivers to use them to record duty status (49 CFR 395.8(a) (opens in a new tab); Part 395, Subpart B (opens in a new tab)). The deadline was December 18, 2017.
Some drivers may still use paper logs. Exceptions include drivers who need a record of duty status on no more than 8 days in any 30-day period, certain driveaway-towaway operations, and vehicles manufactured before model year 2000 (49 CFR 395.8(a)(1)(ii) (opens in a new tab)).
ELDs record when a truck is moving and connect to the engine. But drivers can still mislabel time, for example logging driving as off duty or "personal conveyance." Federal rules prohibit false reports and tampering with an ELD (49 CFR 395.8(e) (opens in a new tab)).
How hours of service violations are found
A log is only one piece of the picture. Investigators often compare it with other records to look for gaps or conflicts.
ELD data. Duty status changes, engine hours, vehicle miles and location data.
Supporting documents. Carriers must keep bills of lading, dispatch and trip records, expense receipts related to on-duty time, fleet messaging records and payroll records for each driver (49 CFR 395.11 (opens in a new tab)).
Fuel receipts. A fuel purchase in one city at a time the log shows the driver resting somewhere else can reveal a problem.
Toll and weigh station records. Where they exist, electronic toll and weigh station bypass records may show where the truck was and when.
Dispatch records and messages. These can show the schedule the carrier set and whether it was realistic within legal limits.
Bills of lading and delivery receipts. Pickup and delivery times can show how long a trip took.
ECM and GPS data. Engine and telematics data may show speed and movement that conflict with the log.
Phone records. These may show the driver was awake and active during time logged as rest.
If the schedule the carrier assigned could not be completed legally, the carrier's own decisions may be at issue, not just the driver's. Our guide on who is liable in a truck accident explains how responsibility can extend to the company.
What to do if you suspect driver fatigue
Get medical care. Your health comes first.
Write down what you saw. Weaving, drifting over lines, slow reactions or a driver who seemed drowsy can all be worth noting.
Record the truck's details. Company name, USDOT number and trailer number, if you can do so safely.
Find witnesses. Other drivers may have seen the truck before the crash.
Preserve the records. A preservation letter can ask the carrier to keep ELD data, supporting documents and dispatch messages. Learn more in our guide to truck accident evidence.
Consider talking to a lawyer before giving a recorded statement to the trucking company's insurer.
Arizona law
Arizona incorporates federal motor carrier safety regulations, including Part 395, by reference and applies them to all intrastate and interstate motor carriers operating in Arizona (A.A.C. R17-5-202 (opens in a new tab)). The Arizona Department of Transportation adopts these rules under A.R.S. 28-5204 (opens in a new tab). For intrastate commerce, the state definition of a commercial motor vehicle generally covers a vehicle or combination with a gross vehicle weight rating or gross weight of 26,001 pounds or more, compared with 10,001 pounds for interstate commerce (A.R.S. 28-5201 (opens in a new tab)).
Arizona law also includes some intrastate exceptions. For example, drivers primarily hauling construction materials and equipment to or from an active construction site within 75 air miles of their normal work reporting location, drivers primarily transporting groundwater drilling rigs, and certain public utility drivers may restart their hours-of-service calculation after 24 or more consecutive hours off duty. The construction exception does not apply to drivers hauling placarded hazardous materials (A.R.S. 28-5234 (opens in a new tab)).
In Arizona, a person who violates a statute enacted for the protection and safety of the public may be found negligent per se. That principle applies only when the law requires or forbids specific acts, not when it sets only a general standard of care, and the injured person must still prove the violation caused the harm (RAJI Negligence 1 (opens in a new tab), citing Good v. City of Glendale, 150 Ariz. 218 (App. 1986), and Reyes v. Frank's Service & Trucking, LLC, 235 Ariz. 605 (App. 2014)). The instruction notes it can be adapted for regulations as well as statutes. Whether a particular hours-of-service violation is treated as negligence per se or as other evidence of negligence depends on the rule and the facts.
Deadlines still apply. Most Arizona injury lawsuits must be filed within two years after the cause of action accrues (A.R.S. 12-542 (opens in a new tab)). Under Arizona's comparative fault law, your recovery may be reduced if you were partly at fault, but it is not barred (A.R.S. 12-2505 (opens in a new tab)).
If you are a truck driver
Hours of service rules protect truck drivers too. If you are a driver who was pushed to break the rules or hurt in a crash caused by someone else, see our guide for injured truck drivers.
To learn more about how a Phoenix truck accident lawyer investigates fatigue and logbook issues, start with a free case review.
Talk to a Phoenix truck accident lawyer for free
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Frequently asked questions
How many hours can a truck driver drive in a day?
Under 49 CFR 395.3, a property-carrying driver may drive up to 11 hours, but only within a 14-hour period that starts after coming on duty following 10 consecutive hours off duty. Some exceptions apply.
What is the 30-minute break rule?
A driver may not drive after 8 cumulative hours of driving without at least a 30-minute consecutive interruption. Off-duty, sleeper berth or on-duty not-driving time can count toward the break. Drivers who qualify for the short-haul exceptions are excepted (49 CFR 395.3(a)(3)(ii)).
What is the 34-hour restart?
A driver's 7-day or 8-day period may end with the start of an off-duty period of 34 or more consecutive hours, which resets the 60- or 70-hour weekly limit (49 CFR 395.3(c)).
Can ELD logs be falsified?
Federal rules prohibit false duty-status reports and prohibit tampering with an ELD so it does not accurately record data (49 CFR 395.8(e)). Even so, logs can be checked against fuel receipts, toll records, GPS data and dispatch messages to look for gaps or conflicts.
Does Arizona have its own hours-of-service rules for trucks that never leave the state?
Arizona incorporates the federal hours-of-service rules in 49 CFR Part 395 by reference and applies them to both intrastate and interstate motor carriers operating in Arizona (A.A.C. R17-5-202). For trucks used in intrastate commerce, the state definition of a commercial motor vehicle generally starts at 26,001 pounds (A.R.S. 28-5201). State law also lets certain intrastate drivers, such as some construction, groundwater drilling rig and public utility drivers, restart their hours-of-service calculation after 24 or more consecutive hours off duty (A.R.S. 28-5234).
How long are truck driver logs kept?
Motor carriers must keep records of duty status and supporting documents for at least 6 months (49 CFR 395.8(k)), and a backup copy of ELD records for 6 months (49 CFR 395.22(i)). After that, they may be discarded unless the carrier has been asked to preserve them.