I attended a rock concert recently, and my ears did not enjoy it. They began to hurt as soon as the band started to play. Now, granted, I'm not exactly an avid concertgoer--you're about as likely to find me in a mosh pit as on an alien space ship--but my ears' aversion surprised me. This was, after all, an outdoor concert, and I was sitting relatively far from the stage. But as I learned, amphitheater speakers that are many hundreds of feet away may still produce noise levels that can be hazardous to your hearing.
Noise is one of those health threats that many of us don't take very seriously, but we should. Exposure to loud noise is thought to be a contributor to hearing loss in about half of the estimated 28 million Americans who have it. Damage can occur from short-term exposure, but typically it's due to the daily, chronic assault on our ears from multiple sources.
One of those sources is public transportation. A study in the August issue of the American Journal of Public Health finds that noise levels from New York City subways are high enough to cause hearing loss in people with regular exposure. 
On average, subways had noise levels of about 80 decibels (dBA). The highest levels--up to 102 dBA--were found on platforms. That's about the same as the noise level from a chainsaw. By comparison, normal conversation is about 65 dBA and a whisper is 30. (Each increase of 10 dBA corresponds to a 10-fold increase in loudness.)
According to the researchers, exposure to 100 dBA for as briefly as two minutes a day could lead to hearing loss in some regular riders. Longer exposures to 90 or 95 dBA-- levels found on many of the subway trains--could have a similar effect.
If you're tempted to try to drown out the noise with your MP3 player, think again. Cranking the volume up to high on your favorite Metallica or Twisted Sister tune can produce noise levels of 100 dBA or higher. The result is that you've traded one potentially hazardous exposure for another.
A better solution when you're encountering the subway, concerts, or any other noisy environment is to wear protective earplugs. For more tips, watch this segment. And see what one former punk rocker is doing to raise awareness of noise-related hearing loss.
