hearing loss

1. HEARING PROTECTION IS FOR EVERYONE!
How we hear: The outer ear acts like a
satellite dish that collects sound. Sound
enters the ear through the pinna (1).
Sound travels through the ear canal (2) in
the form of sound waves (vibrations).
Sound waves strike the eardrum (3) in the
middle ear causing it to vibrate.
The three small bones in the middle ear
(4) vibrate and send the vibrations to the
inner ear.
The vibrations are relayed to a snail
shaped cochlea (5) inside the inner ear.
Inside the cochlea, the vibration is
changed into an electrical signal by the
movement of hair cells The signal is
carried to the brain and interpreted as
sound (6).
1
2
3
4
5
6

2. Damage to Hair Cells
 It Is Painless!
o Exposed to Loud noise over long periods
damage the hair cells in the inner ear. These
hair cells break and can never grow back
again!
 it Is Progressive!
o The longer the ear is exposed, the more
cells are destroyed.
 It Is Permanent!
o Damaged hair cells cannot be repaired.
 It Is Totally Preventable!
 Use your hearing protection
Normal Hair Cells Damaged Hair Cells

3. TYPE OF EAR_PROTECTION
 Flange type plug must be used if noise is higher than 85dB. Handle may be
visible from the front. Flange should not be sticking out
 Earmuffs must be used with the above flange type protectors (double hearing
protection) where noise levels is above 95-105dB.
CORRECT INCORRECT