Hearing scientists are concerned about the potential for many people to experience hearing loss as a result of our increasing use of digital music players. While there?s been a concern among audiologists since the creation of ?walkmans?, today?s MP3s can hold thousands of songs and have longer-lasting batteries than older portable devices. As a result, people are listening for much longer periods of time. Because hearing damage is directly related to the duration of exposure as well as the loudness level, audiologists are primarily concerned that the steady, long-term exposure to even moderately loud music could contribute to premature hearing loss. In fact, there are now young people in their twenties whose hearing tests like that of a typical fifty-year-old.
There are other concerns as well. Many people are listening to their iPods or other MP3s during public transportation in buses and airplanes, where the typical noise levels already exceed ?safe hearing levels?. Experts recommend that music in MP3s be played for no more than sixty minutes at no more than 90 decibels (dB), which is about two-thirds of the maximum volume of most popular devices. Public bus transportation already has a volume level of 90 dB and airplanes may be as loud as 120 dB, causing people to play their music at even louder levels to drown out the transportation noise.
There are two ways that noise exposure leads to hearing damage. The inner ear is equipped with tiny hair cells which are responsible for hearing. Brief exposure to extremely loud sounds, like gunfire (typically 165dB), instantly wears out the hair cells and can cause permanent damage. Consistent, prolonged exposure to even moderate-level loudness (as in music above 90dB played often and for hours at a time) also wears out the hair cells, causing hearing impairment. It?s important to note that when inner ear hair cells are damaged by noise exposure -- like a loud concert (120 dB) or an indoor football stadium with cheering fans -- they typically recove! r after a couple of days of rest. With repeated prolonged exposure to loud sounds; however, the hair cells do not recover easily. Eventually the hair cells die, leading to permanent hearing loss.
MP3s are fairly new, and accumulated noise damage can take years before it causes noticeable problems, so there is not a significant amount of data yet to know for certain how much hearing loss might be attributable to music players. Enough concern over the risk is driving research and an increasing market for noise-canceling headphones which partially or fully eliminate background noise, so you can hear the music better at lower volumes.
Recently a blog posting by Pete Townshend, guitarist for the rock band The Who, warned the iPod generation about the dangers of hearing damage, and said he blames his own severe hearing loss on years of using studio headphones. According to Mr. Townshend, Hearing loss is a terrible thing because it cannot be repaired?If you use an iPod or anything like it, or your child uses one, you MAY be OK? But my intuition tells me there is terrible trouble ahead.
There are steps you can take to reduce your risk of hearing loss.
Borrow or invest in a decibel meter (digital sound meter) to check the loudness levels in your environment, including your MP3 player. Decibel meters cost approximately $50 or less and can be purchased in electronics stores. Do not exceed about 60% of your MP3?s volume capability. Turning the dial just beyond halfway should be your loudness limit.
Use this rule of thumb: If you have to remove the headphones to hear people talking to you at normal conversational level (40 dB), you music is too loud.
Limit your listening time to one hour or less per day, unless you turn the volume down significantly. Invest in noise-reducing or noise-canceling headphones
Have your hearing periodically checked by an audiologist, speech pathologist, or your physician.
Accent On Business founder and CEO Ellen Dunnigan is a seasoned voice and s! peech co ach for business professionals. For nearly two decades, Ellen has coached leaders, entrepreneurs, sales people, media personalities, amateur speakers, and those with voice issues to become more charismatic and influential. She is locally and nationally known for helping leaders give voice to their vision, and for creating confident, memorable, and credible speakers.
Ellen Dunnigan is a masters prepared speech-language pathologist with specific training in voice, English, foreign-accent reduction, and neurolinguistic programming. She is nationally certified by the American Speech-Language Hearing Association.
Dunnigan offers more advice on professional communication and public speaking skills on her website http://www.AccentOnBusiness.net.
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