Transcript Hearing_Conservation.ppt

Hearing
Conservation
Effects of noise
 Causes
hearing loss
 Amount
of damage depends
upon the intensity of the noise
and duration of exposure
 Noise-induced
hearing loss can
be temporary or permanent
1a
Effects of noise
 Prolonged
exposure generally
causes permanent damage
 Noise-induced
permanent
threshold shift is not
reversible/cannot be medically
treated
1b
Effects of noise
 Noise-induced
hearing loss
typically starts with hearing
threshold shifts in the higher
frequencies
 The
type of hearing loss can be
identified and measured with
audiometric examination
1c
Noise hazards
 Noise
is unwanted/unpleasant
sound that may have a negative
effect depending on:
• loudness/frequency
• duration of exposure
• how old/healthy person is
2a
Noise hazards
 Sound
is measured by:
• frequency
• intensity
2b
Noise hazards
 Noise
types include:
• wide band
• narrow band
• impulse
2c
Noise hazards
 Hearing
protection must be
provided when noise exceeds
an eight-hour time-weighted
average of 85db
Noise hazards can
cause:
 Drowsiness
and irritability
 Inability
to hear important
instructions
 High
blood pressure, ulcers,
headaches
2d
Noise hazards can
cause:
 Sleeping
disorders
 Temporary
or permanent
hearing loss
2e
Engineering controls
 Isolate
noisy machinery in a
separate area
 Place
machinery on rubber
mountings
 Use
tiles
sound-absorbing acoustical
3a
Engineering controls
 Arrange
work schedules to
reduce employee exposure to
noise
 Inform
supervisors of
unpleasant/unacceptable noise
levels
3b
Hearing protection
 Factors
taken into account
when selecting hearing
protection devices include:
•
•
•
•
noise hazards
noise frequencies
fit and comfort
noise reduction rating
4a
Purpose/procedure for
audiometric testing
 Checks
a person’s hearing
 Trained
technician uses an
audiometer to send sounds
through headphones
5a
Purpose/procedure for
audiometric testing
 Person
being tested responds to
the sounds when they are first
heard
 Chart
records responses
5b
Hearing protection
makes common sense
 You
are ultimately responsible
for your own hearing
 You
have the most to lose if you
suffer hearing loss
 Make
sure earplugs fit properly
6a
Hearing protection
makes common sense
 Have
an annual hearing test
 Keep
hearing protection devices
in good operation
6b
Hearing protection
makes common sense
 Don’t
use homemade hearing
protection devices
 Wear
hearing protection devices
at work as required
6c