Truck Driver Fatigue

Truck Accidents Caused by Driver Fatigue

Drowsy driving is always dangerous, but the dangers are even more severe when the tired person is a truck driver. Too many truckers continue to drive when tired for economic reasons or due to pressure from their employers. Federal and state laws restricting hours of service aim to combat this problem, but these regulations are not always followed and are not always effective.

Driving a large truck takes specialized skills, things like shifting, making wide turns, controlling a big rig in bad weather conditions, using air brakes. This is why truckers must train for and pass the CDL (Commercial Drivers License) exam. Nevertheless, driver-related errors contribute to a full 31 percent of fatal truck accidents. And the NTSB says that fatigue alone is responsible for up to 40 percent of all truck accidents.

When a truck accident occurs with a tired driver, not only does the size of the truck make serious injuries more likely, but the fact that the driver may be asleep at the wheel also exacerbates the risk. Because a fatigued or sleepy driver is less likely to take evasive actions like braking or swerving, the truck driver is more likely to crash head-on or at high speeds. This can have devastating consequences.

If you have been injured in a truck accident in South Carolina and believe that drowsy driving was a factor, contact an experienced truck accident lawyer at the Louthian Law Firm today. When you entrust your truck injury claim to us, you get 80 years of experience on your side. Schedule your free consultation by contacting us online or by calling us at (803) 454-1200.


Driver fatigue significantly lowers reaction time. In fact, The Adelaide Centre for Sleep Research published a study indicating that a driver who has been awake for 17 hours is just as impaired as a driver with a blood alcohol content of 0.05 percent. If a driver operates a vehicle after being awake for 24 hours straight, then it is as if he or she had a blood alcohol content of 0.10 percent – above the legal limit.

Despite the fact that fatigued driving is so dangerous, many truck drivers persist in trying to operate their vehicles even after they have passed the point of fatigue. Commercial truck drivers are trained in fatigue management. Not only that, they are subject to regulations designed to prevent drowsy driving. So why do truckers stay behind the wheel even when they are too tired to safely drive a big rig?

A Journal of Public Health Policy study helped to shed light on why a driver would continue to drive when tired. According to the study, around two-thirds of truck drivers who violated maximum hours-of-service laws or who operated vehicles when fatigued did so for economic reasons. These drivers continued to drive because of tight schedules, financial need, traffic jams and inclement weather.

The Driver Fatigue and Alertness Study (DFAS) conducted by the FMCSA also took a look at driver fatigue and revealed that there was little correlation between objective measures of a driver’s performance and the driver’s subjective assessment of whether he or she was tired. In other words, truckers tend to think they’re more alert than they really are. The study, which began in 1989, is the largest and most comprehensive study of the effects of fatigue on over-the-road truckers to this day. In addition to demonstrating that drivers were not able to accurately measure how tired they were, the study also looked at the key factors that contributed to making a driver too tired to drive safely.

According to the FMCA assessment, three major factors influenced a truck driver’s level of fatigue. These included:

  • Time of day – This was the most significant factor influencing fatigue and alertness, with drowsiness increasing significantly during the eight hours stretching from late evening until dawn.
  • Duration of driving – The study revealed that the number of hours of driving, or time on task, was not a consistent predictor of observable driver fatigue. However, drivers were better able to avoid lane drift when driving for only 10 hours than when driving for 13. Cognitive performance also suffered after 13 hours of driving.
  • Cumulative days of driving – The study revealed some evidence of cumulative fatigue in multiple-leg trips.


In an attempt to address many of these issues, regulations have been passed that limit the number of hours a truck driver may operate a vehicle. The limitations on drive time are found in Part 395 of the Federal Motor Carrier Safety Regulations. The Federal Motor Carrier Safety Administration enforces the guidelines and has published a summary called Interstate Trucker’s Guide to Hours of Service.

According to the Guide to Hours of Service, the regulations must be followed by drivers of trucks or tractor-trailers involved in interstate commerce which have a weight exceeding 10,001 pounds (with loaded cargo), as well as any trucks or tractor-trailers that are transporting hazardous materials.

These regulations have recently been revised and became effective in July of 2013. The new rules include the following:

  • Drivers can work 70 hours per week if their company operates seven days per week. This is a change from the prior rule allowing 82 hours of work time within a seven-day period. A driver who takes off at least 34 consecutive hours can restart the 70-hour work limit.
  • Drivers whose employers do not operate vehicles every day of the week are capped at 60 hours of driving in a seven-day period. However, the 34-hour restart also applies.
  • Truck drivers must take a break of at least 30 minutes during every eight-hour period of driving.
  • Drivers who work the maximum number of permitted weekly hours must take at least two nights of rest between 1 a.m. and 5 a.m.
  • Drivers have an 11-hour daily driving limit. This reflects no change from the prior maximum drive time rules.
  • If unexpected adverse driving conditions such as fog or a road closure occur, drivers may drive for up to an extra two hours. However, the conditions must truly be unexpected, so a traffic jam during rush hour would not count.

With these regulations, the government has attempted to make sure that truck drivers get sufficient rest and do not drive for excessive amounts of time to make more money or to keep their employer happy. They estimate that the changes would save 19 lives and prevent approximately 1,400 crashes and 560 injuries each year. Nevertheless, under pressure from business, unions and other organizations, in 2014 Congress began considering amendments which would suspend the limit on how often the 34-hour “restart” or rest period can be taken and eliminating the requirement of two periods of rest between 1 a.m. and 5 a.m. during this “restart.”


In order to avoid the serious risk of an accident, it is imperative that truck drivers follow the hours-of-service guidelines closely. Failure to do so can significantly increase the risk of an accident. In fact, studies, including a May 2011 report published by the FMCSA called Hours of Service and Driver Fatigue: Driver Characteristics Research, have revealed the correlation between the number of hours driven and the odds of a crash. According to the FMCSA report:

  • There is a consistent increase in the likelihood of a crash beginning with the fifth hour through the 11th hour behind the wheel.
  • The highest crash odds are in the 11th hour of driving. However, there is also a significant increase in the danger of a crash when comparing the sixth hour of driving to the first four.
  • When driving breaks occur, the odds of a crash are reduced by 32 percent for drivers of full truckloads and by 51 percent for drivers with less than full truckloads.

An analysis of real-world crash situations also highlights the serious dangers a fatigued truck driver poses. For instance, the FMCSA Large Truck Crash Causation study showed that driver fatigue was a factor in 13 percent of large truck crashes caused by the driver.
Based on the study results, the FMCSA indicated in an analysis brief that “Fatigue, drinking alcohol, and speeding are major factors in motor vehicle crashes overall. Although their presence does not always result in a crash, these three factors, as well as other driver, vehicle, and environmental factors, can increase the risk that a crash will occur.” A detailed report from the study reiterated that “[d]river fatigue is a prominent factor, ranking sixth on the driver list with 13 percent of the truck drivers coded as being fatigued at the time of the crash.”


Truck drivers have a responsibility to drive in a reasonably careful and cautious manner to avoid causing a traffic crash or injuring others on the roadways in South Carolina. If a driver violates the maximum hours-of-service requirements, evidence of this violation may be sufficient proof that the driver was negligent in the eyes of the law. Even if a driver doesn’t violate drive time regulations but is still careless in making a choice to drive when he or she is too tired to do so safely, that driver may still be considered negligent and liable for damages.

The trucking company could also be held liable for an accident caused by a fatigued driver. The company can be held responsible for its own negligence if it failed to enforce hours-of-service regulations or if it encouraged drivers to operate their vehicles for longer than permitted by law.

Getting Help With Truck Accidents Caused by Driver Fatigue

Truck accidents are extremely complicated both because of the large amounts of money often involved and because of the potential for multiple defendants. It is important to consult with a qualified tractor-trailer accident to make sure your rights are protected.

If you or a loved one has been injured in a truck accident by a trucker who ignored the rules and instead drove according to his or her own clock, contact the Louthian Law Firm today – We’ll be on the case . . . around the clock. You can reach the Louthian Law Firm at (803) 454-1200 or through our online query to schedule a free consultation.