Study Examines Reasons for Large Truck Accidents

Large, over-the-road tractor trailers keep the nation’s economy running, hauling all types of freight across the country. But because of their sheer size, plus the weight of their cargo, large commercial trucks pose a significant danger to others on the road when they are involved in accidents.

The typical end result of large truck accidents appears obvious: more weight, and therefore more energy and inertia, lead to catastrophic consequences.

But what are the leading causes for truck accidents? A research study released in 2007 by the Federal Motor Carrier Safety Administration and the National Highway Traffic Safety Administration provides the answer to that question.

Truck Accidents Included in National Survey

The study examined reasons for serious accidents involving trucks with a gross vehicle weight rating over 10,000 pounds. In the time period studied, April 2001 to December 2003, 120,000 accidents involving large trucks occurred. Researchers chose to review 963 accidents, which included 1,123 large trucks and 959 passenger vehicles and resulted in 249 deaths and 1,654 injuries. Seventy-seven percent of the trucks in these crashes were tractors pulling a trailer and 5 percent of the trucks were carrying hazardous material. And almost three-quarters of the crashes studied, 73 percent, involved a large truck hitting another vehicle.

The data that researchers used in examining these truck accidents was exhaustive. They interviewed participants and witnesses of the crashes, reviewed the truck drivers’ logbooks, inspected their rigs, and examined the crash scenes. In all, each crash investigation included up to 1,000 data points, from the condition of the drivers before the crash to condition of the road and weather at the time of the crash.

After reviewing all the data, the researchers identified three key variables for determining the risk of truck accidents:

  • Critical Event – what happened that made the accident unavoidable
  • Critical Reason – what caused the Critical Event
  • Associated Factors – the condition of the vehicles, road, weather, and the drivers involved in the accidents

Critical Reasons for Large Truck Accidents

By examining the sample size of 963 crashes, the researchers estimated that the Critical Reason for 87 percent of all large truck crashes nationwide during the study period was tied to the driver. The researchers broke this down further to four categories:

  • Non-performance – the driver fell asleep or was impaired for another reason
  • Recognition – the driver was inattentive or distracted
  • Decision – the driver was driving too fast for conditions or followed other vehicles too closely
  • Performance – the driver reacted poorly, panicked or overcompensated

The vehicle was estimated as the Critical Reason for 10 percent of the accidents, and environmental conditions were assigned to the remaining 3 percent.

Of the Associated Factors assigned to each large truck crash:

  • Brake problems – 29 percent (largest percentage)
  • Traveling too fast for conditions – 23 percent
  • Over the counter drug use – 17 percent
  • Inadequate surveillance – 14 percent
  • Driver fatigue – 13 percent