The majority of hearing loss in the U.S. is due to exposure to loud noise. Noise-induced hearing loss is, painless, progressive, permanent and PREVENTABLE! How loud is too loud? Any easy rule of thumb is that if while you are speaking to someone who is 3 feet away and you have to raise your voice, you are probably in a listening environment that is loud enough to cause damage. If you have ever attended a live concert where the music was loud and after the concert noticed that your hearing was muffled or that you experienced tinnitus (ringing in your ears), that was an example of a temporary threshold shift in your hearing. It was temporary because a few hours later or even the next day hopefully you were able to hear normally again and the tinnitus subsided. Repeated exposure to loud noise can result in permanent threshold shift.
The answer for dealing with noise induced hearing loss is simply to prevent it by wearing personal hearing protection (ear plugs or ear muffs or a combination of the two). Sometimes I am asked about the possible damage from iPODs or MP3 players. Can listening to these devices cause permanent hearing loss? Absolutely! It is a question of how long you listen and at what volume. If you have one of these devices you may want to use the 60/60 rule. Limit your listening to 60 minutes and make sure the volume control is set at or below 60%.