What is Noise-Induced Hearing Loss?

Noise-induced hearing loss (NIHL) is a potential risk of overexposure to loud noises. These sounds can damage parts of the inner ear, leading to difficulty in hearing. In our day-to-day lives, we experience sound from a variety of sources such as household appliances, traffic, and radio and television.

As long as these sounds are at safe levels and don’t last for prolonged periods, they won’t cause NIHL; however, it’s important to be aware that prolonged exposure or overly loud noises can have negative consequences for your ears.

Noise-induced hearing loss (NIHL) can be an immediate or gradual condition, and it can range from temporary to permanent. It can affect one or both ears, and the effects might not be noticeable right away.

Over time, NIHL can cause difficulty understanding other people when they speak, particularly in noisy environments like telephones or crowded rooms. Fortunately, there’s one simple step everyone can take to prevent noise-induced hearing loss: guard yourself against loud noises.

Who is affected by NIHL?

Noise-induced hearing loss (NIHL) can occur in individuals of any age and gender. According to a Centers for Disease Control and Prevention study involving hearing tests and interviews, at least 10 million adults (6 percent) in the United States under age 70 possess features of their hearing tests that suggest they could have NIHL in one or both ears.

An additional estimate suggests as many as 40 million adults (24 percent). The data available also indicates potentially 17 percent of adolescents aged 12-19 having potential evidence of NIHL.

What causes NIHL?

Noise-induced hearing loss (NIHL) happens when an individual is subjected to intense, short-term and/or loud, continuous noise. This could be a single blast of sound, such as an explosion, or consistent exposure to high levels of noise across a long period of time; for example, in an environment like a woodworking shop.

The ability to be exposed to noise-induced hearing loss (NIHL) can increase through participating in recreational activities such as target shooting, hunting, snowmobiling, and playing loud music with earbuds or headphones. Additionally, the use of heavy machinery at home like lawnmowers, leaf blowers, and woodworking tools can also contribute significantly to NIHL. It’s important to be aware of these risks when engaging in any of these activities.

Hearing loss can be caused by sounds at or above 85 decibels (dBA) after long or repeated exposure. The higher the volume of the sound, the quicker this damage is likely to occur. On the other hand, noises under 70 dBA are considered unlikely to cause hearing loss, even with extended period of exposure.

A reference guide to some of the average decibel ratings of everyday sounds is presented below:

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

It is essential to maintain proper hearing protection by limiting the timeframe and proximity of exposure to loud noises. To reduce potential harm, it’s recommended to stay clear from excessively loud noises which are too close or extended in duration.

How can noise damage our hearing?

In order to understand how loud noises can cause damage to our hearing, it’s important to know the basics of how we process sound. Our auditory nerve is responsible for changing sound waves in the air into electrical impulses and then carrying these signals onto our brain in a complex chain of events.

Recognizing the noise-induced hearing loss mechani What is Noise-Induced Hearing Loss?, Greenbank Lawyers

sms requires us to look at what is going on behind the scenes.

Source: NIH/NIDCD

Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum.
The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are called the malleus, incus, and stapes.
The bones in the middle ear couple the sound vibrations from the air to fluid vibrations in the cochlea of the inner ear, which is shaped like a snail and filled with fluid. An elastic partition runs from the beginning to the end of the cochlea, splitting it into an upper and lower part. This partition is called the basilar membrane because it serves as the base, or ground floor, on which key hearing structures sit.
Once the vibrations cause the fluid inside the cochlea to ripple, a travelling wave forms along the basilar membrane. Hair cells—sensory cells sitting on top of the basilar membrane—ride the wave.
As the hair cells move up and down, microscopic hair-like projections (known as stereocilia) perch on top of the hair cells bump against an overlying structure and bend. Bending causes pore-like channels, which are at the tips of the stereocilia, to open up. When that happens, chemicals rush into the cell, creating an electrical signal.
The auditory nerve carries this electrical signal to the brain, which translates it into a sound that we recognize and understand.

Stereocilia perch atop sensory hair cells in the inner ear.

Source: Yoshiyuki Kawashima

Hearing is regulated by specialized cells in the inner ear known as hair cells. Damage to or death of these cells due to noise exposure can cause Noise Induced Hearing Loss (NIHL). Unfortunately, unlike birds and amphibians, human hair cells do not regrow after being damaged or killed, meaning that NIHL is a permanent condition.

What are the effects and signs of NIHL?

Noise-induced Hearing Loss (NIHL) can occur if one is exposed to loud sounds over a long period. The changes might not be immediately noticeable, or could even be ignored until the signs of hearing loss become more apparent. In time, it can result in distorted and muffled sounds along with difficulty understanding what other people are saying.

Such damage caused by NIHL combined with age-related decline can eventually lead to severe hearing loss that requires the use of hearing aids for everyday activities like listening, communicating, and socializing.

Noise-Induced Hearing Loss (NIHL) can be caused by extremely intense sounds like explosions and gunshots. These types of NIHL often bring about immediate and permanent damage to a person’s hearing. Other forms of exposure, such as noises that are consistently loud and continual, can lead to tinnitus, which is a ringing or buzzing sensation located in either one or both ears. Temporary NIHL has recently been studied, with findings suggesting potential lasting damage even after the loss of hearing appears to have cleared up.

Can Noise-Induced Hearing Loss be prevented?

Noise-induced hearing loss (NIHL) is the only form of permanent hearing damage that can be completely prevented. By understanding the risks posed by loud noises and practising proper safety protocols, you can avoid any long-term hearing damage. To ensure your long-term hearing health, consider following these steps:

Know which noises can cause damage.
Wear earplugs or other protective devices when involved in a loud activity or noisy work environment (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.
Ask your employers for hearing protection while at work if the environment is noisy.
Be alert to hazardous noises in the environment.
Make family, friends, and colleagues aware of the hazards of noise.
Have your hearing tested if you think you might have hearing loss.

If you know or suspect that you have suffered from noise-induced hearing loss, it is important to seek professional help. The earlier hearing loss is identified, the better the chances of successful treatment, whether it is the use of hearing aids, implants, or other assistive listening devices.

Additionally, filing a claim with us for noise-induced hearing loss may help to provide much-needed financial support towards medical care and other related expenses associated with hearing loss.

What is Noise-Induced Hearing Loss?