Understanding Noise-Induced Hearing Loss

Understanding Noise-Induced Hearing Loss

More than 40 million Americans live with some form of permanent hearing loss, and sadly, most of that hearing loss is preventable. This preventable majority of hearing loss stems from exposure to dangerously loud noises and is called “noise-induced hearing loss”. When you are around loud noise, without hearing protection there is always a chance you are causing lasting damage to your own hearing. Depending on your noise exposure, noise-induced hearing loss can set in quickly or develop over time.

Noise-induced hearing loss is a serious matter. When you don’t protect your hearing, loud noises can damage your hearing in ways that cannot be repaired, and that hearing loss can reduce your quality of life and overall health. Let’s take a look at how noise-induced hearing loss works, and what you can do to protect yourself.

The Delicate Sense of Hearing

Our hearing is dependent on small and delicate sensory cells that live deep within the structure of the ear. While our outer ear collects sound waves vibrating in the air around us, the inner ear is responsible for translating those vibrations into an electrical impulse that is then sent to the brain to be interpreted. The inner ear accomplishes this with the help of tiny sensitive cells called “hair cells” that line a shell-shaped structure known as the “cochlea”. 

Hair cells are topped with microscopic sensory mechanisms called stereocilia. The stereocilia move with the changing pressure of the sound waves and send signals through the hair cell to the auditory nerve and brain which are then translated into meaning. This finely tuned process gives our hearing its wide range and nuance. It also means that our ability to hear is very dependent on the tiny hair cells of the inner ear.

Unlike most other cells in the body, hair cells cannot repair or replace themselves if they are damaged. An injured hair cell is therefore permanently out-of-commission, with each damaged hair cell creating a small gap in our total ability to hear. Science has shown that we begin to notice changes in our hearing when roughly a quarter of our total hair cells are impaired. 

Loud Sounds and Your Hearing

Many factors can cause irreparable damage to your hair cells. Infection, limited blood flow and even some medication may cause hearing damage, but loud noise exposure is by far the most common cause of permanent hearing loss. 

Our hearing is tremendously sensitive,  and especially useful to us in picking up very soft sounds in our surroundings. Very loud sounds, on the other hand, strain these cells. The louder the noise, the harder it stresses the cell, and the quicker it can cause lasting damage.

The way we measure hearing volume is in units called decibels (dB). At 85 dB, about the sound level of a factory floor or a motorcycle, permanent hearing damage can be sustained after 8 hours of continual exposure. This threshold is important for those who work in noisy settings to ensure their time on the job doesn’t hinder their hearing. Louder noises can damage hearing much quicker.

The average rock concert projects sound at around 105 dB and can only be tolerated for around 10 minutes before it begins to permanently damage hearing. Sounds like gunshots and fireworks have volumes around 120 dB and instantly cause harm to our hearing. Sounds that project at very loud levels above 140dB, like jet engines, cause physical pain to the ears in addition to damage. 

Protect Your Hearing

While the world seems to get noisier all the time, you can prevent noise-induced hearing loss by being conscientious about protecting your hearing. Using ear plugs and ear muffs to block excess noise reduces your exposure to dangerous sound levels and preserves your hearing’s sensitivity. 

Worried you may already be experiencing noise-induced hearing loss? Noise-induced hearing loss can make voices and speech sound muffled or unclear. You may find yourself turning up volume levels on devices around your home. Noise-induced hearing loss can even make you less interested in social connection with others by making conversation difficult and less enjoyable.

It is important to get changes in your hearing checked out with your hearing specialist. While most hearing loss is permanent, it is also treatable. Addressing hearing loss early is the easiest time to adapt to treatment and prevent further hearing damage.