Syracuse University Hearing Conservation Program Training

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Syracuse University
Hearing Conservation Program
Training
John Rossiter, Safety Department
Introduction
This training is designed to teach you about the
purpose and benefits of a hearing conservation
program. After completing the training, you should
understand the following:
 The effects of noise on hearing
 The purpose of SU's Hearing Conservation Program
 The proper selection and use of hearing protection
devices
 The purpose of audiometric testing
How We Hear
Sound is measured by its:
frequency
intensity
When we hear a sound this is what actually takes place:
 SOUND WAVES enter the ear canal and cause the eardrum to vibrate.
 VIBRATIONS pass through 3 connected bones in the middle ear
 This motion SETS FLUID MOVING in the inner ear.
 Moving fluid bends thousands of delicate hair-like cells which convert the
vibrations into NERVE IMPULSES.
 Nerve impulses are CARRIED to the brain by the auditory nerve
 In the brain, these impulses are CONVERTED into what we "hear" as sound.
How Noise Affects Health
 A temporary hearing loss can be caused by exposure to loud noise
for a few hours. Fortunately, hearing is usually restored after a period
of time away from noise.
 A permanent hearing loss occurs after the ear has been continually
exposed to excess noise and has gradually become unable to recover
from temporary hearing loss.
There are warning signs that may be indicative of permanent hearing loss:
 inability to hear high-pitched or soft sounds
 trouble understanding conversation, or speech heard over the
telephone
 ringing or roaring in the ears (called tinnitus)
Noise Levels
DECIBELS
85-90
90-100
EXPOSURE
Exposure over a length of time MAY
cause hearing loss. Examples: subway,
loud shout
EFFECTS
Most hearing loss happens over
a period of time - weeks, months
or years. No pain at this level of
exposure.
Exposure over a length of time causes
At this level of exposure, the
hearing loss. Examples: Power mower,
noise can be uncomfortable
air hammer, newspaper press
Tinnitus (ringing in the ears) may
Exposure over a short period of time
occur after an exposure at this
100-130 causes hearing loss. Examples: riveter,
level. Discomfort threshold is
compactor, rock concert
120 dB(A)
140+
A single exposure can cause hearing
loss. Examples: jet taking off, shotgun
Pain threshold.
Hearing Conservation Program
 A Hearing Conservation Program must
include four basic parts:
 Noise Monitoring
 Hearing Protection
 Hearing Tests
 Training
Noise Monitoring
 Area monitoring
– noise meter
 Personal monitoring
– noise dosimeter
Hearing Protection Devices
There are three basic types of hearing
protection devices:
 ear muffs
 ear plugs
 canal caps
Noise Reduction Rating (NRR): a number that
indicates the degree to which that device reduces
noise exposure.
HPD - Ear Plugs
 Light weight
 Can be worn without interference from
eyeglasses, headgear, earrings or hair
 Comfortable in hot/humid environments
 Less expensive than ear muffs
Ear Plug Insertion
 Wash your hands.
 Inspect the ear plugs.
 Roll the plug between your fingers and
thumb, making sure there are no wrinkles or
creases in the plug.
 Reach one hand behind your head and pull
your ear outward and upward to widen the
auditory canal.
 Insert the plug well into the ear and hold it in
place until it expands.
HPD - Ear Muffs
 Provide more consistent protection than
plugs
 One size fits most heads
 Easy to put on and take off
 Good for short jobs
Ear Muff Disadvantages
 heavier than ear plugs
 may be uncomfortable in hot
environments
 eyeglass wearers may not get a good seal
 expensive
 resonate (vibrate) at lower sound
frequencies (<400 Hz)
Wearing Ear Muffs
 Inspect for cracks, tears or other signs of wear.
 Choose eyewear with thin temples so they don't
interfere with the seal.
 Push your hair away from your ears.
 Center the ear muffs over your head and make
sure the seal is tight.
 Adjust the headband so the ear muffs are
resting comfortably on your head. The cups
should be entirely cover your ears.
HPD - Canal Caps
 They DO NOT extend into the ear canal, only
close the ear opening.
 They are NOT designed for continuous, long-
term wearing.
 They do not give you as much protection as
ear plugs or ear muffs.
Ear Cap Insertion
 Wash your hands
 Reach one hand behind your head and pull
your ear outward and upward to widen the
auditory canal.
 Insert the tip of the cap into the ear, firmly
pushing and wiggling them into place
Audiometric Testing
 Audiometric Testing
– Baseline
– Annual retest
A Standard Threshold Shift (STS) occurs when
the hearing threshold has changed by an average of
10 decibels (dB) or more in either ear at 2000, 3000
or 4000 Hertz. If audiometric testing reveals that
you have a STS, you will be notified.
It’s Your Hearing - Protect It!
 Attend annual training
 Get an annual audiogram
 Wear PPE if required
 Avoid long term exposure to noise, both
at home and at work
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