Photos: Stoughton Trailers

Photos: Stoughton Trailers

NASHVILLE -- The efforts of the design and engineering team at Stoughton Trailers to improve the design of the trailer rear underride guard has earned the company the ToughGuard Award from the Insurance Institute for Highway Safety and the respect of Marianne Karth, a survivor of a rear-impact crash that took the lives of two of her daughters.

On May 4, 2013, Karth was driving her full-size sedan when she was struck by a tractor-trailer, sending her car spinning backward into the rear of another tractor-trailer. The tractor-trailer’s rear underride guard could not withstand the crash and detached from the trailer, allowing Ms. Karth’s car to slide backward under the trailer. The trunk of the car went under the rear of the trailer at the outer edge, and the back of the trailer body entered the back seat of Ms. Karth’s car, killing her 17-year-old daughter, Anna Leah, instantly. Mary Lydia, her 13-year-old daughter, died a few days later from her critical injuries.

That tractor-trailer’s rear underride guard met the 1998 Federal underride standards. In 2011, the Insurance Institute for Highway Safety tested underride guards of eight major trailer manufacturers. All of the underride guards tested met the Federal standards of the day, but none of them were able to stop underride on the outer edges -- the so-called 30-percent offset zone.

Subsequent IIHS testing performed in March 2013 -- just two months before the Karth’s fatal crash -- revealed that only one of the eight manufacturers had designed their guard to successfully prevent underride at the outer edges.

Once the IIHS findings were published, Karth began advocating for safer tractor-trailers. She even filed her own petition for an improved underride rulemaking that went to the Department of Transportation on May 5, 2014. In addition, her husband, Jerry, began writing letters to trailer manufacturers and truck fleets, asking them to voluntarily upgrade their standards. Crash stastics show that 2,205 people died in underride crashes in the ten-year period ending in 2014.

At the same time, Stoughton Trailers began developing an improved rear underride guard that would provide underride protection at the outer edges of the rear end of a trailer.

Together with the IIHS and the Truck Safety Coalition, the Karths helped organize an Underride Roundtable at the IIHS’s Vehicle Research Center on May 5, 2016. The event drew nearly 100 participants, including Stoughton Trailers, which introduced its newly designed rear underride guard to the public through a successful crash test during the event.

Stoughton’s newly designed rear impact guard provides underride protection over the full width of the rear end of a trailer, without added weight to the trailer and at no additional cost to the customer. It is now a standard feature on all Stoughton dry van trailers.

Upon learning of Stoughton’s decision to make this improved protection available on all of their new trailers, Karth said, “Stoughton's cooperative efforts to improve the performance of its rear impact guard demonstrates a genuine commitment to safety. Stoughton is to be commended for taking a significant leadership role in design and safety. In my opinion, many lives will be saved as a result of Stoughton’s efforts.” 

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About the author
Jim Park

Jim Park

Equipment Editor

A truck driver and owner-operator for 20 years before becoming a trucking journalist, Jim Park maintains his commercial driver’s license and brings a real-world perspective to Test Drives, as well as to features about equipment spec’ing and trends, maintenance and drivers. His On the Spot videos bring a new dimension to his trucking reporting. And he's the primary host of the HDT Talks Trucking videocast/podcast.

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