We live and work in a very noisy world and prolonged exposure to many common sounds can lead to permanent hearing loss. An estimated 30% of all Americans over the age of 60 have some degree of hearing loss; many of these people's hearing problems have been caused or at least exacerbated by exposure to noise in the preceding years. Noise exposure is not just about how loud a sound is but also how long a person is exposed to it. For example, exposure to a lawn-mover operating at 90 decibels will start to cause permanent damage after 8 hours, whereas operating a jackhammer operating at 105 decibels for just 1 hour will start to cause damage.
MP3 players are commonly used for extended period of time and many people use them with a volume of greater than 95 decibels. According to scientific evidence listening to music at 95dB will start to cause permanent damage after just 4 hours; some MP3 players can produce in excess of 110dB - at that level just 30 minutes of exposure can start causing permanent and irreversible damage.
Some Noise Guidelines:
1) If you need to raise your voice to a shout to communicate to a person who is at arm's length away then the noise level is potentially hazardous
2) If after leaving the noise you have pain, buzzing or ringing (tinnitus) in your ears then the noise was excessive and potentially hazardous
3) After exposure to noise you have difficulty hearing people, or the clarity of speech is poor - again the noise was potentially hazardous
4)If you attend nightclubs, motor races or concerts it is recommended to use ear plugs
5) Check out the noise indicator chart but remember it is just a guide - if in doubt always use appropriate hearing protection!
6) If you can avoid loud sounds then do so, if not then use appropriate hearing protection