Airbags and hearing loss

By Ann Griswold • Published: May 3rd, 2007
Category: Health in a Heartbeat

Air bags can save your life in an automobile accident, but the safety they provide may come at a deafening cost. As many as seventeen percent of accident victims may suffer permanent hearing loss as a result of air bag deployment. This alarming statistic is based on research by Dr. G. Richard Price, a prominent auditory physiologist. Price’s finding, presented recently at the annual meeting of the National Hearing Conservation Association, applies only to American cars with front and side airbags. Foreign cars have smaller, less powerful airbags and may pose a lower risk.

Permanent hearing damage can result from exposure to sounds louder than one-hundred-and-forty decibels. Airbags deploy with an earsplitting bang that well-surpasses this limit. At one-hundred-and-seventy decibels, they’re louder than a gunshot blast and more thunderous than a jet engine at takeoff.

Price used a computerized model of the human ear to monitor the effects of air bag deployment. The model… called the Auditory Hazard Assessment Algorithm for the Human… constructs a movie of the sound impulse as it enters the ear and shows what happens to each anatomical structure in response to the noise. The model shows that hearing damage from airbags is less severe when the car windows are rolled up, contrary to what you might think. This is because the increased cabin pressure stiffens a bone in the middle ear that blocks the transmission of energy, preventing permanent damage to the inner ear.