According to research from the Insurance Institute of Highway Safety (“IIHS”), 280 people in the U.S. lost their lives in 2011 due to cars sliding under tractor trailers. U.S. and Canadian law mandates underride guards to help prevent these types of accidents. However, new research by the IIHS says those guards perform much worse when a vehicle strikes them off-center.
IIHS staged multiple crash tests using parked trailers from eight manufacturers and ramming them with a passenger car at 35 mph. All trailers passed the full-on tests, and seven of eight successfully handled crashes where the car hit just one half of the trailer. When the test was toughened so that the car struck only 30 percent of the trailers’ width, all but one of the trailers permitted the car to plow underneath the trailer. The resulting damage would have most likely been fatal to car occupants in an actual crash.
The IIHS has asked U.S. auto safety regulators to toughen standards, and trailer manufacturers have begun changing their designs in response to the IIHS campaign. But those changes will take years to filter into the fleet of trailers currently on the road.
For a video summary of the tests conducted by IIHS, click here: