Dr. Philip Michael, a British ear, nose, and throat surgeon tested several different convertibles, at 50, 60, and 70 miles per hour and found that in convertibles, drivers are consistently exposed to noise levels between 88 and 90 decibels. Research has shown that repeated exposure to noise levels over 85 decibels can lead to hearing loss. According to Michael’s research the noise comes from a variety of sources, from the sound of the engine, exhaust, and tires, to other cars, and trucks, to even the sound of the wind brushing past you.
While driving slower in a convertible might sound like the answer it may only make the problem even worse. According to Michael, driving slower will increase noise exposure due to the fact that drivers will be forced to spend more time around other cars and trucks, two of the main sources of the loud noises
More studies should be done to test the hearing of drivers before and after a drive, as well as on those who drive in enclosed cars, but right now it looks like convertible owners should think about driving with the top up for awhile.