Why Truck Driver Fatigue is a Serious Problem

Truck Driver Fatigue

The Federal Motor Carrier Safety Administration (FMCSA) cites truck driver fatigue as one of the leading factors contributing to commercial trucking crashes. While tired driving does not always cause a crash, it can dramatically increase the likelihood that one will occur.

Despite the FMCSA’s best efforts to implement rules and regulations to curb fatigue-related truck crashes, truck drivers are often forced to meet unrealistic scheduling expectations imposed by their employers. These tight deadlines can result not only in fatigued driving, but also speeding – a potentially deadly combination.

What is Driver Fatigue?

Driver fatigue is the combination of sleepiness and driving. The risks associated with drowsy driving are alarming—thousands of crashes and hundreds of deaths occur each year in fatigue-related traffic accidents.

According to federal statistics, driver fatigue is a factor in roughly 13 percent of large truck accidents in the U.S. each year. Truck drivers are also more likely than the general population to drive fatigued, according to the Centers for Disease Control and Prevention (CDC), making the issue a common topic of discussion among trucking safety advocates.

Truck Driver Sleep Requirements and Truck Driver Hours of Service Regulations

Commercial truck drivers are required to follow hours of service (HOS) regulations set by the FMCSA. HOS rules are essentially truck driver fatigue laws designed to keep tired truckers off of public roads and to reduce fatigue while driving.

The truck driver HOS requirements place limitations on when and how long truckers are allowed to drive and work. Truckers are supposed to follow these duty limits at all times (unless exempted, see the FMCSA HOS Guidelines for more details):

14-Hour Driving Window: This is typically thought of as a trucker’s “daily” limit even though it is not based on a 24-hour period. A truck driver is permitted a period of 14 consecutive hours in which they may drive up to 11 hours after being off-duty for 10 or more consecutive hours. The 14-hour driving window begins the moment a driver starts any kind of work, not just driving. Off-duty time, including naps or lunch breaks, do not stop the clock on the 14-hour driving window. Once a driver has reached the end of the 14-hour driving window, they are not permitted to drive again until they have been off duty for another 10 consecutive hours, or the equivalent of at least 10 consecutive hours off duty.

  • Real World Example: Joe Trucker starts work at 6:00 a.m. after being off-duty for 10 consecutive hours. Joe Trucker may not drive after 8:00 p.m. that evening (once he reaches14 hours on duty). He may still work after 8:00 p.m., but he cannot drive his truck again until he has been off-duty for 10 consecutive hours.

11-Hour Driving Limit: As described above, a truck driver may only drive for 11 hours within the 14-hour driving window. However, no further driving is permitted, if more than 8 hours have passed since the driver’s last off-duty or sleep period of at least 30 minutes.

  • Real World Example: Jane Trucker comes to work at 6:00 a.m. after 10 consecutive hours off-duty. She drives from 7:00 a.m. until 2:00 p.m., then takes a required 30-minute rest break (more on the 30-minute rest break below). Jane then drives another four hours until 6:30 p.m., at which time she is required to stop driving until she 10 consecutive hours off-duty have passed. She may continue to work so long as she is not driving commercially.

30-Minute Rest Break: A truck driver must take a 30-minute rest break if more than eight consecutive hours have passed since their last off-duty (or sleeper-berth) period of at least half an hour. Meal breaks or any other off-duty time of at least 30 minutes qualifies as a break. This time does count against the 14-hour driving window, as allowing off-duty time to extend the workday could allow drivers to continue to drive long past the time when fatigue becomes extreme.

  • Real World Example: John Trucker started driving immediately after coming on duty. He can drive for eight consecutive hours, take a half-hour break, and then continue to drive another three hours for a total of 11 hours behind the wheel.
Day Hours
Sunday 0
Monday 10
Tuesday 8.5
Wednesday 12.5
Thursday 9
Friday 10
Saturday 11
Sunday 5

60/70-Hour Duty Limit: The 60/70-hour duty limit is often referred to as the “weekly” limit. The 60/70 limit is not based on a “set” week (Sunday through Saturday, for example), rather, the limit is based on a “rolling” or “floating” seven or eight-day period. The oldest day’s hours drop off at the end of each day in calculating the total time on-duty for the past seven or eight days. So if a trucker works a 70 hour/eight-day schedule, the current day would be the newest day of an eight-day period and the hours worked nine days ago would drop out of the calculation. A driver would not be allowed to operate a commercial vehicle until his or her hours complied with their seven or eight-day work period.

  • Real World Example: Joanna Driver has accumulated 67 hours of driving time during an eight-day period.

Since Joanna is operating on the 70-hour/eight-day rule, she is in compliance. Once Joanna reaches the 70-hour limit, she must stop driving until she has taken enough off-duty hours to operate a commercial vehicle again.

34-Hour Restart: Commercial truckers may “restart” their 60 or 70-hour clock calculations after taking 34 or more consecutive hours off-duty (or in a sleeper berth) or a combination of both.

  • Real World Example: Justin Driver follows a 70-hour/8-day limit and works 14 hours per day for 5 days in a row. He has been on-duty for 70 hours. Justin is not permitted to drive again until he drops below 70 hours worked in an eight-day period. However, if Justin’s company allows him to use his 34-hour restart provision, he would have driving time available immediately after 34 consecutive hours off duty and start a new 70-hour/eight-day period.

How Does Fatigue Affect Driving?

According to the CDC, drowsy driving is most common among those who have not had enough restful sleep, though it can also occur among those who work night shifts, use drugs and/or alcohol, or have undiagnosed sleeping disorders like sleep apnea.

It goes without saying that falling asleep behind the wheel is extremely dangerous. But fatigued driving can still profoundly affect one’s ability to safely drive a passenger vehicle or commercial truck.

Drowsiness behind the wheel can:

  • Affect a driver’s ability to concentrate on the road and other vehicles.
  • Slow reaction times in the event that a driver has to brake or maneuver suddenly.
  • Impact a driver’s ability to make sound decisions regarding when, how, and if to operate.

How Do I Know if I am Driving Tired?

If you are tired and spend too many hours behind the wheel, there is nothing you can do to prevent fatigue from affecting driving. This is why truck drivers are required to comply with mandated Hours of Service Requirements to ensure that they stop work to get the rest they need.

The following are common driver fatigue symptoms to watch out for when you are behind the wheel:

  • Frequent yawning or blinking.
  • Difficulty remembering driving the past few miles.
  • Drifting in and out of your lane.
  • Missing an exit.
  • Running over a rumble strip on the side of the road.

Truck Driver Fatigue Statistics

The following driver fatigue statistics for trucks come from the Federal Motor Carrier Safety Administration (FMCSA) Large Truck Crash Causation Study.

Factors Number of Trucks Percent of Total Relative Risk
Vehicle: Problems with Brakes 41,000 29% 2.7
Driver: Driving Too Fast for Conditions 32,000 23% 7.7
Driver: Unfamiliarity with Roadway 31,000 22% 2.0
Environment: Problems with Roadway 29,000 20% 1.5
Driver: Over-the-Counter Drug Use 25,000 17% 1.3
Driver: Inadequate Surveillance 20,000 14% 9.3
Driver: Fatigue 18,000 13% 8.0
Driver: Felt Under Work Pressure 16,000 10% 4.7
Driver: Illegal Maneuver 13,000 9% 26.4
Driver: Inattention 12,000 9% 17.1
Driver: External Distraction 11,000 8% 5.1
Vehicle: Problems with Tire 8,000 6% 2.5
Driver: Following Too Close 7,000 5% 22.6
Driver: Jackknife 7,000 5% 4.7
Vehicle: Cargo shift 6,000 4% 56.3
Driver: Illness 4,000 3% 34.0
Driver: Internal Distraction 3,000 2% 5.8
Driver: Illegal Drugs 3,000 2% 1.8
Driver: Alcohol 1,000 1% 5.3

Of the 19 truck accident factors listed above, 15 are driver-related accident factors. While driver fatigue is a factor unto itself, driving tired can also lead to or exacerbate some of the other factors listed.

For example, driving fatigued can lead to inattention. If a driver is stressed to make a deadline, he or she may be more willing to try and combat their fatigue through the use of illegal drugs.

Driving Tired Affects Everyone, Not Just Truckers

Driver fatigue is not just a trucker issue; drivers of passenger vehicles are also at risk for drowsy driving, especially if they use medication that makes them sleepy, have sleep disorders or are shift workers.

  • Other studies have indicated that driver fatigue-related crashes may cause thousands of deaths every year.**

* Based on average of two years of NHTSA drowsy driving data
** See: Masten SV, Stutts JC, Martell CA. Predicting daytime and nighttime drowsy driving crashes based on crash characteristic models. 50th Annual Proceedings, Association for the Advancement of Automotive Medicine; October 2006; Chicago, IL.
Klauer SG, Dingus TA, Neale VL, Sudweeks JD, Ramsey DJ. The Impact of Driver Inattention on Near-Crash/Crash Risk: An Analysis Using the 100-Car Naturalistic Study Data, 2006; Springfield, VA: DOT; year. DOT HS 810 594.