Big Rig Accidents in Iowa
In the United States, truck combination vehicles that consist of a powered tractor and one or more trailers are known by various names including tractor-trailers, semis, big rigs, eighteen wheelers and semi-tractor trailers. The tractor unit typically has a steering axle and two drive axles.
Depending on how many trailers they are hauling, a big rig can be long and extremely heavy. Starting at 10,000 pounds, many large trucks in use on the nation’s highways can weigh over 26,000 pounds. These heavy trucks present a significant danger to other vehicles on the roads and highways, especially with the inherent risks of speeding, driver error, and fatigue.
Large Truck Accident Statistics in Iowa
The Iowa Department of Transportation monitors and reports on crashes involving heavy trucks on the state’s roads and highways:
| Year | Crashes | Fatalities |
|---|---|---|
| 2006 | 66 | 75 |
| 2007 | 64 | 73 |
| 2008 | 61 | 69 |
| 2009 | 53 | 62 |
| 2010 | 80 | 89 |
| 2011 | 48 | 60 |
| 2012 | 55 | 63 |
| 2013 | 59 | 63 |
| 2014 | 40 | 42 |
| 2015 | 56 | 71 |
After a spike in the number of crashes and fatalities in 2010, Iowa reported a decrease in deaths to 42 from big rig crashes in 2014. However, 2015 saw a substantial rise in this number to 71 fatalities from 56 crashes.
Although the Department has not released detailed traffic statistics for 2016, they have reported that the total number of road fatalities in all types of crashes was over 400 for the year. This is over 27 percent more than the death toll in 2015, and the final count could rival the highest number of fatalities recorded of 411 in 2008.
The Department reported in mid-May 2017 that the number of fatalities had reached 100. Although this is 20 less than at the same time in 2016, it is still more than the five year low in the state.
Accident Contributing Factors
A Large Truck Crash Causation Study was conducted by the Federal Motor Carrier Safety Administration (FMCSA) in association with the National Highway Traffic Safety Administration in 2007. It was based on data from 17 states involving heavy trucks in 963 crashes. These accidents caused 249 deaths and 1,654 injuries.
The FMCSA found that accidents were caused by:
- Trucks running off the roadway or traveling out of their lane.
- Loss of control when driving too fast in dangerous conditions.
- A shift in cargo, causing drivers to lose control of the vehicle.
- Mechanical or system failure in the vehicle.
- Substandard road conditions.
- Rear end collision with another vehicle.
The study also concluded that 87 percent of crashes were due to driver error or non-performance. Brake failure accounted for 29 percent of accidents, and driver fatigue for 13 percent. Many drivers may be working longer hours than the federal regulations of 11 hours per shift.
Hazardous Freight
In a separate study, the FMCSA reported on crashes involving large trucks during the period 2012 to 2016. In 2015, out of a total of 3,709 crashes, 487 trucks released their cargo after impact. Flammable liquids were released in 267 of these accidents. Other hazardous materials carried by big rigs include gases, explosives, chemicals, poisonous and corrosive substances.