Hearing Conservation

Effects of noise exposure – over exposure to noise can permanently damage your hearing.  When noise is too loud, hair cells in the inner ear begin to die and can no longer convert sound vibrations to electrical signals needed by the auditory nerve in order to hear.  Once the damage is done, there is no way to restore it.  Hearing damage risk criteria is based on the amount of time one is exposed to dangerous intensity levels.  If you know you are going to be exposed to loud noises or sounds, it is extremely important and in your best interest to wear hearing protection.

Styles of hearing protection:

  1. Ear Muffs - these devices usually consist of rigid molded plastic earcups that seal around the ear with foam or fluid-filled cushions.  They are held in place with metal or plastic headbands or by a spring-loaded assembly attached to a hard-hat.  The earcups are lined with acoustic material to absorb high frequency energy.
  2. Earplugs - These devices tend to be more comfortable than earmuffs when protection must be used for extended periods.  There are several different types:

    a. pre-molded earplugs – manufactured from flexible materials such as vinyls and cured silicones
    b. formable earplugs – manufactured from cotton or wax, spun fiberglass, silicon putty, and slow recovery foams
    c. custom molded earplugs – most often manufactured from two-part curable silicon putties, although some are manufactured  in vinyl.  Most fill a portion of the ear canal as well as the concha (bowl) portion of the outer ear.  
    ** These can also be used for recreational purposes such as swimming or hunting

  3. Semi-Aural Devices – consist of pods or flexible tips attached to a lightweight headband.  These provide a compromise between earmuffs and earplugs.  The principal use for semi-aural devices is for intermittent conditions where they must be removed and replaced repeatedly.
  4. In-the-ear monitors for musicians – while there are many different types, this custom made device is designed to reduce volume levels evenly to allow the musician to accurately monitor sound at reduces volumes.  For more information talk to the audiologist.