A major auto crash tester plans to start assessing the risk of head whipping upon impact, which it said could lead to air bag changes to protect against the injuries it can cause.

The Insurance Institute for Highway Safety is working to add to its testing a metric for rotational head motion in crashes that it says was originally used by the National Football League to evaluate player helmets.

IIHS says today’s vehicles are generally “excellent” at protecting occupants’ heads in crashes, air bags playing a key role in preventing them from hitting a car’s hard surfaces. 

But in some cases, it said the head whips to the side if it hits a deployed air bag hard, potentially causing a concussion or other injury. The nonprofit organization’s current testing measures linear impacts but not those types of high-speed rotations.

Until IIHS adds the metric to its testing regimens, it encourages automakers to make adjustments with the head-whipping risk in mind. 

“Vehicle manufacturers don’t need to wait to start looking for ways to prevent the head-whipping motions …,” the group said in a press release on its plans.

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