Dive Brief:
- The Insurance Institute for Highway Safety has updated its moderate overlap front crash test to account for variations in rear shoulder belt positions across different vehicles, the organization announced last month.
- IIHS added a new testing metric called the “chest index factors” for rear seat occupants to evaluate the shoulder belt’s position on a dummy’s chest, as well as how much a collision compresses the dummy’s ribcage.
- For vehicles to receive a good rating, there cannot be a higher risk of injury to the chest for rear seat occupants compared to other body parts.
Dive Insight:
The IIHS previously updated its moderate overlap front test in 2022 after its research indicated that the risk of a fatal injury was higher for occupants wearing seat belts in the second row than for those in the front seat of newer vehicles.
That’s largely because automakers have made the front seats safer by adding airbags and more advanced seat belts, which are rarely available for the rear seats of vehicles, the IIHS said.
The new test procedure factors in different shoulder belt heights to accommodate occupants of various sizes. In addition, the IIHS will evaluate the rear seat belt position to see how well it restrains and controls the motion of a crash test dummy during a collision.
The IIHS piloted the new test procedure for the past year to refine it before the changes became official.
“Most of these changes are part of a planned transition that we informed automakers we’d be making before we launched the updated test a year ago,” said Jessica Jermakian, vice president of vehicle research at IIHS, in a press release. “The new scoring eliminates an artificial benefit our initial ratings awarded for a high shoulder-belt position.”
The IIHS noted that its new chest index factors rating does not apply to children secured properly in rear child safety seats, as children seated in the front can be injured by the force of an airbag when it deploys in a collision. The IIHS says the backseat remains the safest place for children in the event of an accident.
The Institute updated moderate overlap ratings for nearly 90 small and mid-size SUVs, small and mid-size cars, minivans, small pickups, large pickups and midsize luxury SUVs.
As a result of the new testing criteria, the ratings of five vehicles, including the 2022 Chevrolet Colorado crew cab and 2023-2024 BMW X3, improved. Eight other models, including the 2022-2023 Ford Ranger crew cab and 2023-2024 Lexus RX, received downgrades.
