(ARLINGTON, Va.) -- What are your chances of surviving a rear-end collision with a modern semi-trailer truck if you're driving a passenger car? Not bad, according to new tests conducted by the Insurance Institute for Highway Safety (IIHS), which show that trucks do a good job of keeping vehicles from sliding underneath them.
But the same can't be said if you hit only a small portion of the truck's rear. In that scenario, the majority of semi-trailers fail to prevent underride.
Most trucks are required to have steel bars -- known as underride guards -- hanging from the back to prevent passenger cars from sliding underneath them. IIHS engineers put semi-trailers from the eight largest manufacturers to the test to see just how well they work.
"All eight trailers prevented underride in the full overlap crash test at 35 miles per hour. All but one prevented the underride in the 50 percent overlap. And only one managed to prevent underride in all three test conditions," says David Zuby, IIHS' chief research officer.
The one exception was a semi-trailer from Canadian manufacturer Manac.
"Manac engineers show it's possible to go much further. If all trailers had guards like the one on the Manac trailer, many of the lives that are lost in underride crashes could be saved," Zuby says.
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