A safety device required on all semitrailers has proven to break in test crashes and in a deadly accident in Middle Tennessee, a Channel 4 I-Team investigation found.
When Paul Warren crashed into the back of a semitrailer during a 50-car pileup on Vietnam Veterans Parkway on Dec 1, 2011, he struck a metal guard that's designed to keep cars from sliding underneath the truck.
But a Channel 4 I-Team investigation found the guard, often called an underride guard or an ICC bar, broke and bent, sending Warren's car underneath.
Warren received massive head injuries and died.
Larry Daniel of Hendersonville's police department oversaw the investigation into the crash. When asked if he thought it would have saved Warren's life if the guard had not broken, Daniel said he is not sure.
"It's hard to say. I think his chances could have been a little better," Daniel said.
Underride guards are made of steel and are bolted, or welded, onto the trailer and hang low to prevent cars from sliding underneath.
Every semitrailer hauling 10,000 pounds or more is required to have them.
A police photograph, obtained by the Channel 4 I-Team, shows the guard came apart at the bolt, and one area where it was welded to the trailer nearly split entirely.
When Warren hit the guard at an angle, it was simply pushed aside, allowing his car to go underneath.
A Channel 4 I-Team investigation found Warren's crash is hardly unique.
And federal death statistics from the National Highway Traffic Safety Administration, or NHTSA, indicate it's a widespread problem. On average, more than 300 people die every year when their car strikes the back of large trucks such as semitrailers.
The NHTSA data doesn't show how many of these cars slid underneath in the fatal crashes, but each were likely to have a guard that's supposed to prevent deaths.
In February 2011, the Insurance Institute for Highway Safety asked NHTSA to start requiring stronger underride guards.
The IIHS set up real-world crashes where different underride guards, all meeting government standards, were struck by a 2010 Chevy Malibu.
The IIHS wanted to see if the guards would work as designed, meaning if a car hit, it would not break and the car's front end would absorb the impact.
But in crash tests, the guards were just pushed back as the car slid underneath, and the dummy in the drivers' seat came in contact with the trailer itself.
"When the guard breaks like that, and is pushed aside by the car, it means there's very little chance for the person in the car to survive a crash like that," said Russ Rader, an IIHS spokesman.
Another test the IIHS ran is significant to what happened to Paul Warren.
Warren didn't hit the back of the truck straight on but instead struck it at an angle, ending up beneath the right rear side.
Crash investigators believe he tried to swerve to miss the truck.
In the additional tests, the IIHS positioned a car to strike a guard in the exact same way Warren's car crashed.
Again, the guard broke, and the test car ended up in the exact same position of Warren's car with the guard bent exactly like in the crash.
The 2010 Malibu used in the tests received the highest crash test rating the IIHS gives.
Warren's 2009 Toyota Carolla also received the IIHS' highest crash test rating.
"When guards fail, these crashes are often catastrophic," Rader said.
The NHTSA also studied the effectiveness of underride guards in 2010 and concluded, based on their investigation, there is not enough evidence to show the guards are even effective at preventing crashes.
It also found while the overall number of fatal crashes is down, there is a proportionally higher number of deaths happening when people strike the rear of a semitrailer.
In a statement to the Channel 4 I-Team, a spokesman for NHTSA said, "NHTSA is aware of the scope and severity of the truck underride issue... we have been conducting an in-depth field analysis to determine how we can improve that standard to save lives."
There's no single manufacturer of these guards and there's no data to show which guards are failing.
But there is a debate brewing if these guards should be strengthened, which would require every semitrailer to be fitted with stronger guards.
Those types of stronger guards were also tested.
On Friday at 6 p.m., the Channel 4 I-Team will show those additional tests to see if the stronger guards performed better, and a U.S. Congressman will weigh in on the I-Team's findings.
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