Understanding What Sound Does To Your Hearing


Suddenly, your family celebration was turned on its head when the firework that was supposed to soar 100 feet in the air and explode into a beautiful array of colors instead went off at ground level.

Luckily for your family, they were all a safe distance away, but lighting the fuse was your job, so you were close—too close. Ten feet, to be exact. Everyone is safe from your pyrotechnic mishap, but boy was it loud, and it left you with sharp pain and a ringing sound in your ears. Loud noises happen, though, so you brushed these issues off, assuming they’d just go away.

Here you are now, one week later: Your ear still hurts, the ringing is still there, and everyone sounds a bit muffled. You decide to go to the doctor, and they discover a perforation—a hole—in your eardrum and tell you it’s what’s causing the pain and hearing loss.

So, what exactly happened? How did this single incident so harshly impact your hearing?

How Hearing Works

Loud noises can cause serious damage to your hearing. This can happen in an instant or due to exposure over a long period of time. But to understand how sound can damage hearing, it’s first important to understand how hearing works.

Let’s break it down.

  1. Sound waves enter the outer ear (pinna) and are directed down the ear canal (external auditory meatus), where they hit and vibrate the eardrum (tympanic membrane).
  2. The eardrum—made up of three epithelial layers of tissue, two of which can heal but with parts (the inner mucosa) that don’t grow back—vibrates from the sound waves coming down the ear canal.
  3. These vibrations travel to three tiny bones: the malleus, incus, and stapes, also known as the hammer, anvil, and stirrup respectively.
  4. These three tiny bones amplify the sound vibrations and send them to the cochlea—a snail-shaped structure filled with fluid and tiny hair cells called cilia.
  5. The vibrations being sent to the cochlea ripple the fluid, thereby stimulating the cilia.
  6. As the cilia ripple, even smaller hair-like projections—known as stereocilia—at the top of each cell bend to the right frequency. When they bend, they create an electric signal with the nerve ending.
  7. The auditory nerve attached to the cochlea sends this signal to the brain, which then interprets the sound into something you know and recognize.
Diagram of the inner and outer ear workings

How To Measure Sound: Decibels and Decibel Range

Sound intensity is measured with a unit called a decibel, abbreviated as dB. Decibel levels fall into a normal range that won’t hurt your hearing, a warning range in which you should limit your exposure or protect your hearing, and an extreme danger range in which you should wear hearing protection if you can’t avoid it altogether.

How Does Sound Damage Hearing?

Each of the cilia—those tiny hair cells—is tuned to a different frequency (pitch). The cells near the opening of the cochlea detect higher-pitch sound waves, while the inner cells detect the lower-pitch sound waves.

Keep in mind that frequency and pitch are separate from decibels; sounds can have a high frequency and low decibel and vice versa.

Concussive Damage

When it comes to loud sounds, concussive noises—such as firework explosions or gunfire—can be especially damaging because right when something explodes, it sends a shockwave out in all directions.

Unlike regular sound waves, shockwaves travel through elastic mediums—such as air, water, or solid substance—and create violent changes in pressure. Also, depending on how big the initial concussion of sound, a shockwave can even be seen by the naked eye. Regular sound waves are not visible.

Why is any of that information important, you ask?

Have you ever seen videos of an explosion that blow out nearby windows? That same kind of damage can happen in your ears if you’re near a violent concussive sound. The shockwave can hurt or rupture your eardrum, damage your small ear bones, or even break your cilia, causing permanent, irreversible hearing loss.

Damage Over Time

When you’re exposed to any noise, the cilia vibrate to pass electric signals to the brain. When you’re exposed to loud noises, those cilia vibrate violently. While they may have the strength to withstand the more intense vibrations for a time, they eventually break down because of overuse — like broken slats on a wooden fence.

When a cilium breaks, the cilia on either side must compensate for it. This may suffice for a short time; however, when enough of the cilia are broken, they can no longer compensate. This is when you will experience noticeable and irreversible hearing loss.

Protect Your Hearing

Many factors play into hearing loss—genetics, disease, and other unavoidable circumstances—but noise-induced hearing loss is preventable. It all comes down to protecting your hearing when in situations with dangerous sound levels, especially if you anticipate them ahead of time.

If you work in an environment—construction, farming, production, military, trucking, etc.—or are going to a club or concert with elevated sound levels, you must take the proper precautions. There are a number of easy things you can do to protect your hearing if you plan ahead, such as wearing over-the-ear muffs or in-ear plugs that block out sound.

If you’re in an overwhelmingly loud situation, try to get as far away from the noise as you can, limit your exposure, and allow your ears time to recover afterward. If you‘re not sure how loud is too loud, remember:

  • When you have to raise your voice to be heard, you might be in the warning level of sound exposure.
  • When you have to shout to be heard or cannot be heard over the noise, you are in the danger level.

There are smartphone apps that can check decibel levels, too; simply go to your app store and search “decibel tracker” or something similar.

CaptionCall Can Help

If you’ve lost your hearing—whether it happened due to noise exposure or other means—and speaking on the phone has become difficult, CaptionCall is here to help you.

CaptionCall offers a true no-cost captioning service to people with hearing loss who need captions to use the phone effectively. The CaptionCall phone works just like your regular phone, except you can hear, see, and read real-time captions of what your caller is saying on a large, easy-to-read screen.

You shouldn’t miss anything on your calls; see if you qualify today!