Noise and Hearing

We may take our ability to hear for granted - until we lose it. Unfortunately, many things in our environment can affect our hearing. (Read about "The Ear and Hearing") Loud and harmful noises at home, at work, and at play can lead to sudden or gradual loss of hearing. The good news, according to the National Institute on Deafness and Other Communication Disorders (NIDCD), is that, by taking precautions, we can reduce our exposure to many of these noises.

How we hear

When sound waves enter the ear, they cause the eardrum to vibrate. These vibrations move to the inner ear, where tiny hair cells help produce nerve impulses. The nerve impulses are then carried to the brain (Read about "The Brain" "Nervous System") and interpreted as sound. (For specific terms, see "Hearing/Speech/Smell/Taste Glossary")

Exposure to loud noises, however, can damage the hair cells. NIDCD says sometimes this can happen all at once. For example, hearing loss or changes may result from exposure to a single loud explosion. (Read about "Hearing Loss") A sudden loud noise can rupture the eardrum. (Read about "Ruptured Eardrum") When hearing loss is triggered in this fashion, it may also be accompanied by ringing in the ears. (Read about "Tinnitus")

Noise-induced hearing loss can also happen gradually over time. For example, continuous exposure to loud noises at work may lead to progressive or sudden changes in the way we hear. Such changes may come on in stages, with sounds becoming progressively muffled or distorted. Hearing loss can sometimes be temporary, but if exposure to the condition that created the hearing loss continues, permanent changes may result.

Prevention

There are three things that impact whether noise harms your hearing. According to the American Academy of Family Physicians (AAFP), it depends on loudness, pitch and the length of time you are exposed. Loudness is measured in what are called decibels (dB). The louder the sound the less time it takes to do damage.

Examples from the AAFP include, 8 hours of exposure to 85dB industrial noise on a daily basis is considered safe for most persons' ears. However, using power tools (at about 100dB), listening to stereo headsets (at about 110dB) or attending a rock concert (at about l20dB) may damage the hearing of some people after only a few times.

Another concern is earbuds. The National Institutes of Health say earbud headphones project sound directly into the ear canal, while traditional earmuff-style headphones allow the sound to diffuse. The proximity of the source of the sound to the ears may contribute to hearing loss.

How can you tell when things are too loud? If you can't understand someone two feet away, if you have to shout to be heard or if someone nearby can hear the music from your headphones, then things are probably too loud.

What you can do

Some suggestions from the AAFP include:

• Avoid excessive noise whenever possible. If you work in a noisy place, try to find as much quiet time as you can outside of work. Going to a rock concert after running a jackhammer all day isn't a good idea.
• Use earplugs. They cost just a couple of dollars but can cut 25dB's off the noise level. You should always use them when riding motorcycles or snowmobiles or using power tools including lawnmowers and leaf blowers.
• Keep the volume down. Don't turn the TV up to drown out the radio or the vacuum. When you're in the car, don't turn the radio way up to drown out the traffic noise. If you are listening to music through headphones, keep the volume low, and avoid listening for extended periods of time.

You should also have your hearing checked regularly. If you work in a noisy place, like a factory, you should have your hearing tested at least once a year. If hearing problems are suspected, an otolaryngologist is the type of doctor who specializes in this area. An audiologist is also trained to measure hearing loss and provide help in coping with the problem.

Related Information:

    The Ear and Hearing