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(Earbuds and Headphones are Fashion Statements!)
By Bethany Webb
Growing up, if your household was anything like mine, “turn it down!” was one of the most common phrases used by adults and siblings alike. Whether it was the TV, the radio, or someone’s personal listening device, it seemed like someone always thought something was too loud. Most of the time, the perception that something was too loud was usually because my sister was trying to study or my mother was trying to sleep. However, I can remember a few angst-filled nights when the radio was too loud because, as a dramatic teenager, I wanted it to be too loud.
Now, as I have matured and entered the field of audiology, I am thankful for the many times I was forced to turn it down. The invention and wild consumption of mp3 players gave researchers an incentive to learn a lot more about what noise can do to hearing. Just five years ago, Sandra Levey, Tania Levey, and Brian Fligor conducted a study about noise exposure in mp3 users. They examined both the sound level and the listening time of 189 college students. Based on their results, approximately 58% of listeners exceed the recommended listening limits every day.
Why is it so detrimental to exceed the recommended limits for noise exposure? Sure, your ears may ring after a rock concert, but after a couple days everything goes back to normal, right? Well, not necessarily. After a loud concert your hearing may feel muffled, but it is common for it to return to normal in a couple days. This is called a temporary threshold shift. And because it is temporary, most experts previously believed that there was no permanent damage done to the ear. However, recent animal studies have shown evidence of damage to up to 50% of the hair-like structures in the inner ear that detect sound and send electrical signals to the brain. The loss of these inner hair cells can affect a person’s ability to understand speech in a noisy environment. Even though someone’s hearing thresholds may not change, their ability to hear in more difficult types of environments is affected. Because the damage done by noise is cumulative, with frequent exposure to loud sounds, that temporary threshold shift can quickly turn into a permanent threshold shift, meaning permanent hearing loss.
So how loud is too loud? According to the National Institute for Occupational Safety and Health (NIOSH), 85 decibels (dB) for 8 hours is the daily limit. For every additional 3 dB, you should cut your exposure time in half. Therefore, you should expose yourself to 88 dB for no longer than 4 hours, 91 dB for no longer than 2 hours, 94 dB for no longer than 1 hour, 97 dB for no longer than 30 minutes, and 100 dB for no longer than 15 minutes. For those of you who do not carry a sound level meter with you wherever you go, here are some common sounds that occur at various sound levels.
So what can you do? The easiest solution is to turn it down. While that may be simple for an mp3 player or a car radio, it may be more difficult to accomplish with a lawn mower. For environmental sounds that do not contain a volume control, hearing protection is a fantastic alternative. Wearing earplugs decreases the level of the sound that reaches your ear and helps protect them from hearing loss. Because hearing loss due to noise is cumulative, it is important to protect the hearing you have. Help yourself, help your family, and help your friends by promoting good hearing health through hearing protection. Your ears will thank you!