Crashing similarities

As an international association with members in 47 countries, SC&RA is concerned about the impact of varying geographical considerations on companies in our industry throughout the world. For example, are there similarities between the main causes of accidents involving trucks in Europe and in the United States? Two recent studies provide an opportunity to begin making useful comparisons.

In the US, the Department of Transportation's Federal Motor Carrier Safety Administration and National Highway Traffic Safety Administration conducted a nationwide study of factors contributing to 967 crashes in 17 states during 2001 to 2003, which included 1,127 large trucks, 959 non-truck motor vehicles, 251 fatalities and 1,409 injuries. The resulting report on the Large Truck Crash Causation Study was released to the US Congress in March 2006.

A little over a year later, the European Commission and the International Road Transport Union published the European Truck Accident Causation Study. This study was based on investigations of more than 600 truck accidents in seven European countries – France, Germany, Hungary, Italy, the Netherlands, Slovenia and Spain.

For all crashes in the US study, driver issues accounted for 87% of the reasons. Similarly, human error was the main cause of 85.2% of accidents involving heavy trucks in Europe. Crashes in both studies most frequently involved failure to correctly recognize the situation or poor driving decisions.

In the US, the most common associated driver factors included legal drug use (prescription and over-the-counter), travelling too fast for the conditions, unfamiliarity with the roadway, inadequate surveillance, fatigue and feeling under pressure from motor carriers. In Europe, the top main causes for accidents between a truck and other road users were non-adapted speed, failure to observe intersection rules and improper manoeuvring when changing lanes.

In all two-vehicle crashes involving a large truck and a passenger vehicle in the US, the passenger vehicle was assigned the critical reason in 56% of the crashes and the large truck in 44%. The European study showed that, of the accidents linked to human error, only 25% were caused by the truck driver and the other 75% were caused by the other road user.

In crashes between trucks and passenger vehicles in the US, driving too fast for the conditions and fatigue were important factors cited for both drivers; however, fatigue was coded twice as often for passenger vehicle drivers, and speeding more often for truck drivers.

In the US, 13% of the truck drivers were coded as being fatigued at the time of the crash. The European study found fatigue was the main cause in only 6% of the accidents but 37% of these accidents were fatal.

The European study pointed out the difficulties in proving that fatigue was the main cause of the accident. “There are various stages of vigilance from slight fatigue to sleeping, and fatigue is often linked to other causes such as being inattentive,” noted the report. “Last but not least, the experts can only base their judgement on what they saw at the accident scene and what the drivers and witnesses told them.”

Such analysis becomes all but impossible when there are neither witnesses nor surviving drivers. Moreover, the criteria for judging fatigue may vary between enforcement and research officials in Europe and the US.

For that matter, overall differences in the methodologies between the two studies make valid comparisons difficult in many other ways. It really does feel like comparing apples and oranges.

SC&RA believes that the US, Europe and other regions should work closely together on future studies. For example, researchers could design commonalities into their questionnaires and databases. The results might help reveal regulations, enforcement practices, infrastructure conditions and other factors that work in one nation, which could apply to another nation's to help prevent crashes.