Audiologists: Leading the Fight Against Noise-Induced Hearing Loss

• By School of Health Professions
• August 20, 2020

Noise-induced hearing loss affects a significant proportion of the US population. Fortunately, unlike many other causes of hearing loss, it is completely preventable.

According to Leigh Ann Reel, Director of the Center for Speech, Language, and Hearing Research at Texas Tech University Health Sciences Center School of Health Professions (TTUHSC SHP), upwards of 24% of adults and 12% of children suffer from some degree of hearing loss caused by exposure to loud noise.

In spite of the high prevalence of noise-induced hearing loss across the general population, Reel believes that audiologists can face an uphill struggle in persuading people to protect their hearing.

“Although most people understand that exposure to loud noise can cause hearing loss, many people still choose not to wear hearing protection,” says Reel. “This most likely happens because noise-induced hearing loss typically develops gradually over a period of years, so people don’t realize their hearing is being damaged at first.  People often think that hearing loss due to noise exposure is something that only happens to “older people,” but exposure to loud noise can cause permanent damage to hearing at any age.”  

What Causes Noise-Induced Hearing Loss?

Noise-induced hearing loss is caused by loud noise damaging the sensory hair cells in the inner ear.

“The little sensory cells move in response to sound,” says Reel. “They are very delicate. When you’re exposed to a loud sound, it over-stimulates those little sensory hair cells. Initially, it may over-stimulate them so that they swell and temporarily don't work as they should. Because of these changes, you may notice difficulties hearing and ringing in your ears.  Most people have experienced this type of temporary threshold shift after being exposed to loud noise, such as music at a concert or shooting guns.”

Over time these symptoms typically improve, and the person will perceive that their hearing returned to “normal.” However, Reel states that each episode can cause small amounts of permanent damage to a person’s hearing and over time, the effects become cumulative.

“People think their hearing is going back to normal after each episode, so they continue doing those noisy activities over and over again without properly protecting their hearing,” says Reel. “They don't realize that they may actually be left with a small amount of permanent damage to their hearing each time they experience a temporary threshold shift. The changes may be so small that they aren’t perceptually noticeable to the person until years later.”

Reel explains that once the sensory hair cells in the inner ear are damaged they do not grow back.
“Damaged hair cells are replaced by scar tissue,” says Reel. “The person will then begin having difficulties hearing in those pitches where the hair cells have ruptured and died.”

Can a Hearing Aid Help?

Reel suggests that many people ignore the possibility that they are damaging their hearing through prolonged exposure to loud noise because they believe a hearing aid will restore their hearing should it be damaged. While hearing aids can help a person with noise-induced hearing loss, a hearing aid is not a miracle cure.

“Many people with noise-induced hearing loss can benefit greatly from hearing aids,” says Reel. “However,  it’s important to understand hearing aids cannot restore a person’s hearing to normal. A hearing aid still has to send the amplified sound through a damaged ear, so sounds will never be as clear as they are to a person with normal hearing.”

Research into Preventing Noise-Induced Hearing Loss

Reel suggests that research into preventing noise-induced hearing loss is currently a long way from finding a cure.

“Research is looking at the use of otoprotective drugs that may help prevent noise-induced hearing loss,” says Reel. “However, this research is primarily with animals, so there’s a long way to go before —  or if  — it can be used with humans.’"

In the meantime, education is the audiologist’s main weapon in the fight against noise-induced hearing loss.

“It’s important for people to know how loud noise has to be to damage hearing,” says Reel. “A quick rule of thumb is that if you have to raise your voice to speak with someone who is only an arm’s length away, the noise is most likely loud enough to potentially damage your hearing.  In other cases, such as in work settings, it’s important to have a very accurate measurement of noise levels. These measurements can be performed by an audiologist using a sound level meter.”  

Reel also explains that there are several apps available that can be downloaded on a smartphone and used to monitor sound levels.

“There are numerous sound level meter apps, but they are not all equally accurate,” says Reel. “One that is supported by research is the NIOSH Sound Level Meter app from the National Institute of Occupational Safety and Health. However, to be most accurate, it’s important to have the app calibrated by an audiologist using a sound level meter, but even without calibration, it can provide a rough estimate of the noise level.”

Reel states that exposure to noise levels above 85 decibels can be potentially damaging to hearing, depending on the length of time the person is exposed.

Where Do Audiologists Work?

Audiologists help prevent noise-induced hearing loss through education and research across a range of settings including universities, hospitals, private practices, ear, nose, and throat physician’s offices, and public schools. They are also employed by industries where employees may be exposed to loud noise as well as by organizations like the U.S. Department for Veteran’s Affairs (VA).

The Bureau of Labor Statistics (BLS) states that audiologists can expect to earn a median annual wage of around $75,920. Job prospects are good with a predicted 16% job growth increase in the profession by 2028.

Learn more

To learn more about TTUHSC SHP's Doctor of Audiology program, or to speak with a member of our faculty, please visit the program page on our website.