According to the World Health Organization, environmental noise is now being acknowledged as an important public health issue and a top environmental risk faced by the world today.
One of the casualties of the noisy world we live in is noise-induced hearing loss (NIHL). NIHL can be caused by a one-time exposure to an intense “impulse” sound, such as an explosion, or by continuous exposure to loud sounds over an extended period of time, such as noise generated by a lawnmower, a leaf blower or other loud power tools.
Recreational activities that can put you at risk for NIHL include target shooting and hunting, snowmobile riding, listening to MP3 players at high volume through earbuds or headphones, playing in a band, and attending loud concerts. Harmful noises at home may come from tools we commonly use including woodworking tools, vacuum cleaners and hair dryers.
NIHL can be temporary or permanent, may affect one or both ears and it may be immediate, or barely noticeable.
What is clear is that exposure to harmful noise can happen to anyone at any age—children, teens, adults and older adults. Based on a 2011-2012 Centers for Disease Control study involving hearing tests and interviews with participants, at least 10 million adults (6%) in the U.S. under age 70—and perhaps as many as 40 million adults (24%)—have features of their hearing test that suggest hearing loss in one or both ears from exposure to loud noise. Researchers have also estimated that as many as 17% of teens (ages 12 to 19) have features of their hearing test suggestive of NIHL in one or both ears (Pediatrics 2011), based on data from 2005-2006.
Most NIHL is caused by the damage and eventual death of the tiny hair cells in the inner ear. Unfortunately, once these hair cells are damaged, they don’t regenerate or grow back, resulting in hearing loss.
How loud is that sound?
Often, we underestimate just how loud sounds are, or how much damage they can do, even in short bursts. Sound is measured in units called decibels. Sounds at or below 70 A-weighted decibels (dBA), even after long exposure, are unlikely to cause hearing loss. However, long or repeated exposure to sounds at or above 85 dBA can cause hearing loss. The louder the sound, the shorter the amount of time it takes for damage to hearing to occur.
Decibel ratings for some familiar sounds are:
- Normal conversation: 60-70 dBA
- Movie theater: 74-104 dBA
- Motorcyles and dirt bikes: 80-110 dBA
- Music through headphones at maximum volume, sporting events, and concerts: 94-110 dBA
- Sirens: 110-129 dBA
- Fireworks show: 140-160 dBA
Your distance from the source of the sound and the length of time you are exposed to the sound are also important factors in protecting your hearing. A good rule of thumb is to avoid noises that are too loud, too close, or last too long.
With technological advances, it’s also possible to download a decibel app on your smartphone that can measure how loud a sound is. Simply search for “decibel meter” in the app store to find possibilities. These apps may not be 100% accurate, but they can give you a good idea of how loud your surroundings are.
For example, a quiet rural area might log in at 30 dBA, while a bird singing might clock in at 45 dBA. Neither of those sounds is loud enough to cause any damage to your hearing, but over time, consistent exposure to much louder sounds might be an issue.
Exposure to loud noise also can cause tinnitus, better recognized as a ringing, buzzing or crickets in your ears. In fact, tinnitus is often the first sign that damage has occurred to your hearing. Sometimes tinnitus subsides, but it also can be so severe it interferes with daily life.
Preventing NIHL
The only type of hearing loss that is preventable is NIHL. In addition to being aware of how loud sounds are around you, you also should follow these tips from the National Institute on Deafness and Other Communicative Disorders.
- Wear earplugs or other protective devices when involved in a loud activity (activity-specific earplugs and earmuffs are available at hardware and sporting goods stores).
- If you can’t reduce the noise or protect yourself from it, move away from it. Putting extra distance between you and the loud noise, say a fireworks display, can help reduce the loudness and potential damage to your hearing.
- Be alert to hazardous noises in the environment.
- Take extra caution to protect the ears of young children.
- Have your hearing tested if you think you might have hearing loss.
If your occupation or hobbies require you to be exposed to loud noises, be sure to wear hearing protection. Foam earplugs, earmuffs, or a combination of the two can greatly reduce your exposure to loud noises and save your hearing.
Custom hearing protection also is available for musicians, concert goers, hunters, recreational vehicle drivers and many others. This type of hearing protection does require a consultation with an audiologist for custom ear impressions.
If you think you may already have hearing loss or may be at risk for NIHL, consult an audiologist for a comprehensive hearing evaluation.
