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					 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


  ??

				
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