Hearing Loss and Air Bags

by Neil Bauman, Ph.D.

Air bags save lives—and for that we are definitely thankful. They also destroy hearing—and that is not so nice. Here is Lisa’s story.

Last week I was involved in what should have been a minor car accident. I wasn’t paying attention and “gently” hit the car in front of me stopped for a light.

What happened next was terrifying. The inside of the car seemed to explode in a deafening roar. I had an unimaginable pain in both ears and considerable bleeding from my ear canals. I also had a very loud ringing and was virtually deaf.

I was taken to the hospital where it was quickly determined that my eardrums had ruptured. I was referred to an ENT who said they should heal in 2-3 weeks, but possibly with scar tissue that would affect my ability to hear low sounds. As for the ringing, he said that could be permanent. He also said I had suffered inner ear damage that would affect my high-frequency hearing, although he said it was hard to tell how much. He concluded by saying I would need to face life “hearing impaired” and may need to look at hearing aids.

I have always protected my hearing and never would have thought about going to loud concerts or auto races without effective noise protection. I’m only 22 and I can barely hear conversation in a quiet room. With background noise, I am almost deaf.(1)

Lisa is not alone. Many other people have also experienced tinnitus and/or hearing loss when air bags deploy. In fact, the results of researcher Richard Price’s studies indicates that a whopping 17% of the people exposed to deployed air bags will experience permanent hearing loss. That’s a lot of people—almost 1 in every 5 people exposed to air bags going off!

Here’s another surprising discovery. His data also shows that contrary to what experts previously thought, airbag deployment is more damaging to our ears when we have the windows rolled down.

This is because the higher pressure generated in the closed cabin actually prevents greater damage to the ear. The pressure causes a displacement in the middle ear that stiffens the stapes, a small bone outside the inner ear. This stiffening limits the transmission of energy to the inner ear, where hearing damage takes place. In airbag experiments where the cabin is completely sealed and pressure is even higher, hearing damage is reduced even further.

Incidentally, Price’s study only included cars sold in the United States. American cars have larger, more powerful airbags than cars sold in Europe. Hence, cars with smaller airbags sold in other parts of the world would likely pose less auditory danger when tested under identical circumstances.(2)

The moral of the story, and another good reason to drive carefully and avoid accidents, especially “fender benders,” is that an air bag going off causes just as much damage to your ears whether you are going 15 miles an hour (and serious injuries are unlikely) or 80 miles an hour (where hearing loss may be the least of your worries)!
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(1) Hearing Loss Web Forum: Issues: Air bags ruined my life. Accessed online at http://www.hearinglossweb.com/discus/messages/12/733.html?FridayJune1020050444pm.

(2) As reported in The Hearing Review 2007-07-10. Taken from: Price Richard. Intense impulse noise: hearing conservation’s poison gas. Paper presented at: Annual Conference of the National Hearing Conservation Association, February 16, 2007.