Protect Your Hearing

If sound feels uncomfortable or painful to your ears, it probably is.  You should always pay attention to your body’s warning system; your ears are telling you that the sound is causing damage.  Excessive decibel levels and prolonged exposure to them will damage the sensory cells in the inner ear that are necessary for our ability to hear.

How does the ear work?

Any source of sound sends vibrations (sound waves) into the air which are picked up by your ear and funneled into your ear canal.  In there, they will strike the eardrum and cause it to vibrate.  These vibrations are then transmitted through the tiny bones in the middle ear to the auditory hair cells of your inner ear, and further on to the part of your brain which interpret these vibrations as sound such as music, speech or noise.

When the sound is too loud, it may kill the hair cells in your inner ear; as the exposure time and/or the loudness level increases, more and more haircells will get destroyed.  As their number decreases so does your hearing, and there is no way to restore dead hair cells as they cannot be healed or regenerated.  The damage to your hearing is now irreversible and results in permanent hearing loss.

When does sound become dangerous?

People differ in their sensitivity to sound.  As a rule of thumb, if you have to shout over background noise to make yourself heard, this background noise may be capable of harm as the level will be approximately 85dB(A) or more.  The higher the sound levels, the higher the risk of damaging your hearing.

Very loud sounds of short duration such as gunfire or an explosion can be painful and can produce immediate severe to permanent hearing damage. On the other hand, noise levels between 80 -120dB can produce painless damage to your hearing and you may not be aware of it at the time, but you may notice too late, when it is done. The longer the exposure time the higher the risk of damage to your hearing.

When should I wear hearing protection?

You should wear hearing protection when you are in excessively noisy environments with noise levels above 80db(A).

The information below shows how easy it is to exceed maximum exposure time:

Some noise level examples (estimates):

The longer the exposure time, the more damage may be caused to your hearing .

How can I tell if my hearing is already damaged?

Hearing loss usually develops over a period of time - generally years - and since it is painless and gradual, you might not notice it.  Signs of damage are when the noise hurts, or makes your ears ring, or slight deafness for some time after the exposure to loud sound.  Hearing impairment associated with excess sound exposure can occur at any age.  Regular hearing checks will provide you with up-to-date information on your current hearing capabilities.

Images of an inner ear (cochlea):

Normal inner ear:

No indication of any damage to the inner ear.

(Scanning Electron Micrograph H.Engstrom/ B.Engstrom - courtesy of Widex APS)

Scanning electron micrograph showing the hair cells of a normal ear

(Scanning Electron Micrograph H.Engstrom/ B.Engstrom - courtesy of Widex APS)

Damaged inner ear:

Damaged inner ear - notice that the innervations in the mid region of the cochlea is blank or damaged.

(Scanning Electron Micrograph H.Engstrom/ B.Engstrom - courtesy of Widex APS)

A micrograph demonstrating the damaging effect of noise to cochlear sensory cells.
The inner hair cells (IHC) are seen forming one row with well preserved sensory hairs, while the outer hair cells (OHC) are severely damaged with many cells missing and other cells showing irregularly arranged cilia.


(Scanning Electron Micrograph H.Engstrom/ B.Engstrom - courtesy of Widex APS)