Download Hearing Loss Prevention

Listen Up!
Hearing Loss
Prevention
Written by: Christy Bryan, Amanda Stephens
& Dr. Frank Flanders
Art by:
Randy Glance & Mark Smith
Reviewed by: Janet Ehlers of the National
Institute for Occupational Safety
& Health
Georgia CTAE Resource Network
Revised April 2010
Go To: Test Questions
Note to Teacher: See ‘Notes’ section of the PowerPoint for additional information.
Enduring Understanding
Preventing hearing loss is of vital importance
on the job as well as in everyday life.
Permanent hearing loss can occur much easier
than most people realize. Once hearing is
damaged, it is damaged forever!
Essential Questions
• What sounds and sound levels may
damage hearing?
• How can hearing loss be prevented?
• What is the proper use of hearing
protection devices?
• How could hearing loss impact you in the
future?
• How can sound be measured?
Measuring Sound Levels
• A decibel (dB) is the unit used to measure
sound levels.
• A dB measures how loud sounds are and how
the sounds will affect hearing.
• The higher the dB level, the louder the sound.
Activity I
Instructions: Rank the following sounds from 1 to 8 with 1
being the sound least damaging to the ear and 8 being the
most damaging to the ear. Check your answers on the next
slide.
•
•
•
•
•
•
•
•
Rock band
Hand drill
Squealing pig
Gunshot
Firecracker
Circular saw
Chainsaw
Normal conversation
1.
2.
3.
4.
5.
6.
7.
8.
____________
____________
____________
____________
____________
____________
____________
____________
Source: “Have You
Heard? Hearing Loss
Caused by Farm Noise is
Preventable” Produced by
Department of Health and
Human Services, CDC, and
NIOSH
Return to Test Answers
Activity II
Instructions: Rank the following sounds from 1 to 8
with 1 being the sound least damaging to the ear
and 8 being the most damaging to the ear. Check
your answers on the next slide.
•
•
•
•
•
•
•
•
Chop saw
Circular Saw
Hand drill
Orbital sander
Miter saw
Router
Chainsaw
Hammer drill
1.
2.
3.
4.
5.
6.
7.
8.
____________
____________
____________
____________
____________
____________
____________
____________
Source: “Have You
Heard? Hearing Loss
Caused by Farm Noise is
Preventable” Produced by
Department of Health and
Human Services, CDC, and
NIOSH
Return to Test Answers
Source: “They’re Your Ears
Protect Them- Hearing Loss
Caused by Farm Noise is
Preventable” Produced by
Department of Health and Human
Services, CDC, and NIOSH
Length of Exposure
• Long or repeated
exposure to sounds at
or above 85 decibels
can cause hearing loss.
The louder the sound,
the shorter the time
period before noise
induced hearing loss
can occur.
Hearing Loss Facts
• Hearing loss can be temporary or permanent.
• Hearing loss can occur at any age.
• Nothing can restore permanent hearing loss. Once
it’s gone, it’s gone!
• All types of equipment and tools can cause
hearing loss.
• When hair cells in the ear are damaged
they do not grow back--unless you’re a
reptile!
Parts of the Ear
Source: National Institute of Health
Auditory Nerve
• The auditory nerve connects the inner ear to
the brain. It transports information from the
cochlea to the brain.
Cochlea
Source: National Institute of Health
• The Cochlea is the part of
the inner ear that is shaped
like a snail.
• The inner ear is lined with
hair cells that are too tiny to
be seen without a
microscope. They are called
stereocilia.
• There are 18,000 hair cells
per cochlea.
• All 18,000 hair cells would
fit on the head
of a pin.
Undamaged Stereocilia
Source: National Institute of Health
Stereocilia Are:
• Fingerlike projections
• They rock back and
forth with the sound
waves.
• They transmit messages
to the brain, which is
how a person
hears sound.
Damaged Stereocilia
Source: National Institute of Health
• The stronger the sound
waves the greater
damage inflicted upon
the ear.
• Once damaged,
stereocilia can not be
repaired.
• Damaged stereocilia
causes hearing
loss.
How can hearing be protected?
1. Turn down the volume of:
•
•
•
MP3 players
Radio/Stereo systems
TV
2. Walk away from loud noise
3. Wear a hearing protection device
4. Control the noise by adjusting equipment,
blocking or deflecting the noise, etc.
Hearing Loss Prevention Devices
Earplugs- Formable
Earplugs- Premolded
Canal Caps
Earmuffs
Ear Plugs
• Ear plugs come in different
sizes and should fit snugly
into the outer ear canal
(auditory canal).
• For people who need them
frequently, such as people
who are regularly exposed
to job-related noise, they
can be custom-made for a
better fit.
• You also can buy disposable
ear plugs.
Application of Formable Earplugs
Proper way to insert earplugs
1. Roll
2. Reach
3. Insert
4. Hold
Source: “Tips and tools for
fitting and using foam earplugs”
by Elliott Berger
Inserting An Earplug
If the earplug looks similar to this then it is:
Ear Muffs
• Ear muffs cover both
ears entirely. When
they fit properly and
are held in place by a
headband, they form an
air-seal that reduces
the volume of sound
entering the ears.
Canal Caps
• Canal caps are worn
under the chin not over
the head.
• Canal caps are
convenient: they can be
worn around the neck
when not in use.
Check the Noise Reduction Rating
• When purchasing hearing protection, always
be sure to check the Noise Reduction Rating
(NRR) number on the package.
• The NRR number is the measure, in dB, of
noise reduction.
• The NRR can be twice as high as the
protection you will actually get. Keep this in
mind when selecting hearing protection.
• If hearing protection is
worn, but not worn
correctly, damage to
hearing may still occur.
• Be sure to read all
instructions and
warnings on the
packaging.
• Follow all
manufacturer’s
instructions.
Activity Three: Purpose
• To demonstrate the permanent damage to
hearing (stereocilia damage) caused by loud
noises.
Source: www.Dangerousdecibels.org
Activity Three: Shake It, Break It
1. Place 3-5 pipe cleaners in
one hand and at the
bottom make a fist around
them as shown. The pipe
cleaners represent the
hair cells in your inner ear
(stereocilia) that may be
damaged and cause
hearing loss.
Source: www.Dangerousdecibels.org
Activity Three Continued…
2. Gently move your hand so
that the pipe cleaners sway
slightly. This represents low
to medium noises and
music.
3. Move your hand a little
faster so that the pipe
cleaners sway more without
bending. This represents
border-line noises or music.
Source: www.Dangerousdecibels.org
Activity Three Continued…
4.
Move the pipe cleaners vigorously so that they sway
forcefully and bend over. The more violent you shake the
better. This represents the effect of loud noises or music.
Source: www.Dangerousdecibels.org
Activity Three Continued…
5.
Try to straighten the pipe cleaners in any manner you
prefer. Try to make them look like they did originally.
6.
You cannot make them as straight as they once were. This
is what permanent hearing loss looks like!
Source: www.Dangerousdecibels.org
Myth and Fact
Myth: A person can’t hear people around them
or the machine or tool they’re using while
wearing earplugs.
Fact: Earplugs block background sound which
may allow you to better hear people around
you and the machine or tool.
Myth and Fact
Myth: Hearing aids correct hearing just like
glasses correct vision.
Fact: Hearing aids will not fully restore
lost hearing.
Myth and Fact
• Myth: The insurance company will pay for a
hearing aid.
• Fact: Many insurance companies will not pay
for hearing aids.
• Fact: Even the best hearing aids, which range
from $3,000-$6,000, do not fully restore
hearing.
Review Questions
• What happened to your model of the inner ear
(stereocilia) in Activity One?
• Do you think doctors can repair the tiny hair cells
(stereocilia)?
• Name three sounds that are loud enough to
damage the ear.
• What can you use to protect your hearing?
• What are some activities in your everyday
life that may damage your hearing?
Test Questions
1. At what dB level does noise become harmful
to hearing?
2. How can you restore your hearing once it is
lost?
3. What does the NRR number tell you on
hearing protection product packaging?
4. Name three tools or pieces of equipment
that can cause hearing loss.
5. What part of the ear is damaged
during hearing loss?
Test Questions Continued…
6. At what decibel level does a normal conversation
occur?
7. True or False: A farmer drives a tractor at 90dB for
30 years, without hearing protection, this will
cause no hearing loss.
8. Can a hearing aid completely restore hearing once
it is lost?
9. Name three devices that can prevent hearing loss.
10. Should an ear plug be rolled or folded before
it is inserted into the ear?
Test Answers
1. 85 dB
2. You cannot restore your hearing once it is lost.
Hearing loss is permanent!
3. The Noise Reduction Rating is the measure, in dB,
of noise reduction.
4. Refer to chart 1 or chart 2: some answers may
include gunshot, tractor, firecrackers, chainsaw,
hammer drill, etc.
5. The “hair cells” or stereocilia are damaged.
Test Answers Continued…
6. A normal conversation occurs at 60 dB.
7. False. Even though the noise is only 5 dB higher
than 85 dB, the continuous noise over a long period
of time may cause hearing damage.
8. A hearing aid cannot fully restore hearing once it is
lost. It simply amplifies the sounds through a
microphone.
9. You can prevent hearing loss by wearing hearing
protection devices, walking away from the noise,
and turning the volume level down.
10.Three types of hearing protection devices
are: ear plugs, ear muffs, and canal caps.