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Hearing Protection

Hearing Dosimetry
Employees (or their supervisors) who believe that they are exposed to high levels of noise may request a noise evaluation by submitting a request for assessment.
Exposure to high levels of noise can cause temporary or permanent damage to hearing. Damaging levels of noise can be caused by a wide variety of sources such as construction equipment, heavy machinery, lawn mowers, weed wackers, steam generation, concerts, and industrial or agricultural vehicles. The University of Maryland is required to evaluate potential noise exposure and implement precautions to protect affected employees.

The UMD Hearing Conservation Program establishes the procedures to be followed to evaluate, control and monitor noise exposures. Requirements for training, hearing tests and hearing protection are established in this program.

Employees who are exposed to full shift (eight hour) average noise exposures more than 85 decibels must be enrolled into the Noise Exposure Medical Surveillance Program through the University Health Center - Occupational Health. Contact (301) 314-8199 to enroll into the program after excessive noise exposure is demonstrated.

Noise level assessment usually starts by measuring noise levels with a Sound Level Meter. The Occupational Safety & Health Unit at DES uses either of the two instruments shown below:
Type Two Sound Level Meter

If noise levels are shown to exceed 85 decibels, full-shift noise dosimetry is usually conducted utilizing a Metrosonics db3100 dosimeter:

Metrosonics db3100 dosimeter

This device is worn by the employee for the entire shift, with the microphone placed near either ear. At the conclusion of the shift, noise level data is retrieved and analyzed to determine if noise is excessive.


Employees who are exposed to full-shift noise levels more than 85 dB must be provided with hearing protection that will attenuate (reduce) noise levels to 85 dB or below. Hearing protector selection is based on many factors including comfort, type, size, method of use and their tested ability to attenuate actual noise levels. Occupational Safety staff at DES must approve the specific type(s) of hearing protection worn by employees.
Employees in the Hearing Conservation Program must receive annual training to understand the risks and methods of protection. Training is provided by DES during regularly-scheduled classes or by special arrangement for on-site education.

Noise dosimetry (monitoring) has been conducted for many occupations at the University of Maryland. A summary of noise dosimetry that has been conducted during the past several years is available.

Noise dosimetry has proven that employees working in the following areas must be enrolled into the Hearing Conservation Program:
   Facility Management - Grounds
   Facility Management - Life Safety
   Facility Management - Piped Services
   Facility Management - HVAC Zone 3
   Facility Management - HVAC Zone 4
   Facility Management - HVAC SCUB OPS
   Facility Management - HVAC Fume Hood Shop
   Facility Management - HVAC MSS (formerly Scheduled Maintenance)
   Facility Management - Suez (Central Seam Plant)
   Dining Services - Dishwashers in South Campus Dining Commons
   Agriculture Experiment Stations
   Public Safety


Noise levels have been assessed in most of the mechanical rooms across campus. Signs are posted at entrances to warn entrants if hearing protection may be necessary. A sample of one of these signs follows:

Hearing Protection Required Sign

If new equipment is added to the room, or if older equipment is removed, please notify DES of the changes to initiate a new survey of the affected space(s).

The database of mechanical room noise levels is available for review.

Manuals, Guidelines, Policies


Forms

  • Personal Protective Equipment Form Display PDF Form  Display WordPerfect Form  Display Word Form

Related Sites

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Phone 301.405.3960