Hearing Conservation
Noise Exposure Standard
29 CFR 1910.95
Facilities Planning and
Management
By: Chou Lor, Safety Coordinator
Hearing Conservation
• Training Objectives:
• Provision of Noise Information
• Hearing Safety
• Explain how hearing loss occurs
• Categories of Hearing Loss
• Hearing Prevention Methods
• Noise Hazard Signs
• FP&M Hearing Conservation Program
• Summary
Provision of Noise Information
• What is Noise?
• A sound that is unwanted
because of:
• Intensity
• Frequency
• Duration
• Sound is produced by vibrating objects
and reaches a person’s ears as
waves in the air or other media.
• A vibration in the air transmitted
by the eardrum and bones of the
middle ear to the inner ear.
Noise Risk Factors
Intensity: The loudness of sound, or the pressure it exerts through
the ear.
Noise
Most
Jet Take - Off
Severe Levels:
150 Gun Shot
140
150 Jack-Hammer, Rock Concert
140 130 Car Stereo, Band Practice
130 120
120
Dance Clubs, Headphones
110
110 100
Factory
100 Subway
90 Busy Street 90
80
80 Restaurant
70
70 Normal Speech
60
60 Decibels
Action Level
Least (85 dBA)
Severe
Provision of Noise Information
• Noise Risk Factors Cont.
• Frequency
• Frequency is the number of sound waves
(high and low pressure areas) produced by a
noise source passing a given point per second.
• Duration
• The amount of time you are
exposed to a sound level.
− Continuous such as:
– Music, grinders, engineers running
− Impulse
– It should not exceed 140 dBA peak sound pressure level
as measured by an impulsive type sound level meter.
– Example, Pneumatic tools, punch press,
gun shots, firecracker are more damaging
Hearing Safety
• If you have to shout at 3 feet in
order to be understood you should
be wearing hearing protection.
• Off-the-job activities (woodworking,
shooting, etc.) can hurt your hearing.
- Hearing protection is recommended.
• Never remove hearing protection
in high noise areas.
• Do NOT share hearing protection with others.
Explain how hearing loss occurs
Physiological Effects:
It is noise-induced loss or aural pain,
nausea and reduced muscular control.
Interference Psychological
With Communication Effects:
Effects such as depression
Not being able to communicate Types of and nervousness are a result
well with others can cause
Hearing Effects of the ear’s inability to
arguments, depression, adjust to sound (i.e. disrupt
loneliness, and a sense of concentration of sleep).
helplessness.
Explain how hearing loss occurs
Inner Ear
Outer Ear
Middle Ear
The outer ear or pinna, funnels sound waves into the
Outer ear canal, which will lead to the eardrum. It will catch
Ear dirt and particles in the canal that contains cerumen or
wax.
Human ear Middle Has three tiny bones and ear drum
has 3 Parts Ear which can rupture from sudden
high sound pressure level.
Inner Has cochlea with tiny hair cells connected to
nerves. It signals the brain, which lets you know
Ear
what sound you heard. Damage is irreversible.
Categories of Hearing Loss
• Conductive Hearing Loss:
• Occurs when the sound vibration from the
outer and middle ear is unable to stimulate
the inner ear, due to some form of
interference but the inner ear functions
normally.
• The outer ear is generally susceptible
to physical damage or infection.
• Possible causes of a conductive loss include:
• A build-up of fluid in the middle ear.
• Wax in the ear canal.
• Puncturing of the eardrum.
Categories of Hearing Loss Cont.
• Sensory Hearing loss:
• Damage to or a malfunction of the inner
ear, auditory nerve, or the brain.
• The causes of Sensory Hearing loss:
• Genetic Disorders.
• The natural aging process.
• Exposure to loud noises.
• Infection or other disease.
Categories of Hearing Loss Cont.
• Aging
• Presbycusis:
• The gradual loss of hearing
due to increasing age.
• Two theories of Presbycusis:
• Caused by changes of blood supply to
the inner ear that decreases with age.
• Cumulative effect of noise exposure.
• Exposure to Noise
• Prolonged exposure to loud noise can also
destroy the sensitive hair cells of the cochlea.
• Brief exposure to loud noises (85 dBA or louder)
can also cause a temporary damage.
Categories of Hearing Loss Cont.
• Symptoms of Over Exposure
• Do Not ignore these symptoms:
• Dullness in hearing.
• Ringing in the ear (Tinnitus).
• Difficulty hearing a conversation
against a noisy background.
• Other Dangers of Noise:
• Increased Fatigue, errors.
• Increased Stress and/or irritability.
• Elevated Blood Pressure.
• Decreased Productivity.
Hearing Prevention Methods
• Engineering Controls
• Enclosure
• Provide an easy, secure and effective
way to isolate noisy machines.
• Sound barriers
• Materials used to stop sound from
a noisy machine or equipment.
• Sound proof cabs
• Better design of machinery & equipment, insulate
the machinery to reduce the noise & isolate
workers in soundproof booths.
• Equipment and exhaust
• Proper maintenance of equipment & exhaust prevents the
extra noise of machine & dirty exhaust.
Hearing Prevention Methods Cont.
• Administrative Controls
• Decreasing the exposure time
• Limiting the amount of time a worker spends
in a high noise area to less than 8 hours.
• Limiting the number of personnel exposed
• The number of employees working
in the noisy area should be limited
to the absolute minimum.
• Arranging a work roster system
• A roster system could be arranged
when employees are not working in
the same areas everyday.
Hearing Prevention Methods Cont.
• Hearing Protectors “Earplugs”
• Description
• These devices fit into the ear canal between
the outer and middle ear and block the sound
from reaching the sensitive inner ear.
− Made of foam material that is rolled and inserted,
expands to fit snugly.
• How to fit and wear
• Wash hands, roll and compress into a cylinder.
Reach one hand around the back of the head
and pull ear up and out. Insert into the ear
canal. Hold in place until it begins to expand
and excludes noise.
Hearing Prevention Methods Cont.
• Earplugs
• Care
• Inspect before insertion and
discard if damaged or dirty.
• Advantages
• Small, inexpensive, portable, comfortable
in warm weather, disposable, can
hear others speaking.
• Disadvantages
• Requires a good fit, cannot be inserted
with dirty hands, cannot be worn with ear
infections, might become loose over time.
Hearing Prevention Methods Cont.
• Hearing Protectors “Ear-band”
• Description
• Over the head, in front the neck
and behind the neck.
• Advantages
• Soft pieces pressed against ear
canal by spring-loaded band.
• More convenient than earmuffs.
• Can provide adequate protection.
• Flexible tips.
• Do not extend into the ear canal.
• Only cover canal opening.
• Disadvantages
• May become uncomfortable over time.
• Soft pieces are bulky for some employees.
• Cannot be inserted with dirty hands.
Hearing Prevention Methods Cont.
• Hearing Protectors “Earmuffs”
• Description
• This style protector consists of cups which
fit over the entire outer ear to help seal
out noise. May be connected to the hard
hat or held together by a head band.
• How to fit and wear
• Cushioned caps connected by
a spring loaded headband.
• Adjust the headband to ensure that the seals
are in complete contact with the head. Ensure
the ear cup fits over the entire outer ear.
Hearing Prevention Methods Cont.
• Earmuffs
• Care
• Wipe cushions when they
become soiled. Replace if stiff,
worn, cut or torn.
• Advantages
• Can be worn with ear plugs for extreme
noise exposure. Reduction of approximately
28-50 dBA. Easy to put on and remove.
Can be worn despite ear infections.
• Disadvantages
• Bulky and can be uncomfortable
in warm weather.
Noise Hazard Signs
• Used when engineering controls do not
work, or are not feasible.
• Use Yellow and Black signs to mark
hazards.
• Large signs for entire areas.
• Small stickers for individual equipment.
• Post areas as Hearing Protection
Required if sound levels at or above
90dBA.
FP&M Hearing Conservation Program
• Program requirement:
• Protect workers from risks to
their hearing caused by noise.
• Prevent hearing loss and deafness as
a result of exposure to noise at work.
• Identify noise problems and if
noise levels are above 85dB(A),
measurements must be taken and
assessed by a competent person.
• General duty to reduce the level
of noise exposure by engineering
or administrative means.
FP&M HCP Cont.
• Program Requirement
• If noise level is above 85dB(A):
• Inform employees of the noise levels present
and measures taken to reduce exposure.
• Make ear protection available
and provide training in its use
• Hearing checks must be made available to
employees exposed to noise levels in
excess of 85dB(A) over an 8 hour TWA.
Summary
• Be able to recognize the potential
hazards of noise and its symptoms.
• Be able to use noise control methods
such as Engineering Control,
Administrative Control, and PPE to
avoid exposure to noise
• Wear hearing protection properly
• Proper fit to ensure protection
• Must maintain a good seal
• Readjust as necessary
Any Questions
??