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Where engineering and administrative controls are not successful in lowering noise exposure, hearing protection devices must be used. OSHA requires that employees be offered a variety of hearing protection devices, including ear muffs and ear plugs. If you suspect that you may be over exposed to noise contact the Environmental Health & Safety Office at 515-6862. Noise exposure may be continuous, intermittent or impulsive (less than one second in duration with a delay of more than one second).

Types of Hearing Protectors

There’s a wide variety of types of hearing protectors available, including ear muffs, foam and preformed ear plugs, and canal caps. Selection is based upon several factors, as described below.

Ear Muffs - These devices fit against the head and enclose the entire external ears. The inside of the muff cup is lined with an acoustic foam which can reduce noise by as much as 15 to 30 decibels. Ear muffs are often used in conjunction with ear plugs to protect the employee from extremely load noises, usually at or above 105 decibels.

Ear Plugs - Preformed ear plugs come in different sizes to fit different sizes of ear canals. Formable or foam ear plugs, if placed in the ear correctly, will expand to fill the ear canal and seal against the walls. This allows foam ear plugs to fit ear canals of different sizes.

Canal Caps - As the name implies, these devices cap off the ear canal at its opening. They generally provide less protection than ear muffs or plugs. These devices are not recommended for use by the EHSC.

Choosing a Hearing Protector

Choosing the right hearing protector depends upon several factors:

- Good seal: sound reduction is dependant upon blocking any air leakage which will allow sound to bypass the hearing protector and enter the ear. For this reason, the hearing protector must fit properly whether over the ear or in the ear.

- Comfort: Both comfort and convenience are important if the device is to be used consistently. The ease of placing and removing the device, as well as environmental factors such as the presence of dirt or chemicals must be considered.

-Communication: Hearing protectors often make communication difficult by reducing and distorting sounds. Employees who are hearing-impaired who must receive detailed face to face instruction may prefer ear muffs so that they can lift up the muffs to hear speech.

Correctly Fitting the Device

Ear Plugs - Refer to the diagram for correct insertion of ear plugs. Remember to use the opposite hand to open the ear canal. This is done by grasping the top of the ear and gently pulling upwards. The plug, having been compressed, is placed into the ear canal and held in place for about 10 seconds to allow for expansion of the ear plug.

Ear Muffs - The ear muff cushion must form a seal against the head all around the ear and not rest against any part of the outer ear.

Maintaining a Hearing Protector

Ear plugs must be replaced on a daily basis or whenever they become soiled. Using an unclean ear plug may lead to an ear infection. Employees should be issued their own ear muffs, however, if ear muffs are used by more than one employee, the ear muffs should be cleaned frequently. Ear muffs should be wiped off with soap and water. Ear muffs should be inspected regularly for signs of wear and tear, and should defects appear, the device should be replaced.