Hearing Conservation

Hearing conservation is a program to protect faculty, staff, and student hearing from potentially damaging levels of noise that includes the following components:

  • Hazard Assessment (Noise Monitoring)
  • Audiometric Testing
  • Hearing Protection
  • Employee Training

The Hearing Conservation Program reduces hearing loss exposures for faculty, staff, and students exposed to noise levels of 85 decibels A-weighted stale (dBA) or greater on an eight hour time-weighted average (TWA) basis. After noise sources are identified and monitored, the implementation of engineering, administrative and personal protective equipment controls will reduce campus noise level exposures. Some areas may need to be posted with a sign stating "Caution: Hearing Protection Must Be Worn While Working in this Area."


Who is Responsible for Hearing Conservation?

When the employee suspects there is excessive noise levels in their workplace, refer to the "Rules-of-Thumb" below, the employee must contact their supervisor or EHS immediately. The supervisor must report all employee noise complaints or suspect noise issues to EHS. EHS will conduct a hazard assessment (noise monitoring) on all suspect excessive (hazardous) noise complaints or issues to determine proper noise controls and recommendations such as personal protective equipment.



There are three non-technical rules-of-thumb to determine if the work area has excessive noise levels:

  1. If it is necessary to speak very loudly or shout directly into the ear of a person in order to be understood, it is possible that the exposure limit for noise is being exceeded. Conversation becomes difficult when the noise level exceeds 70 decibels (dBA).
  2. If the employees say that they have heard noises and ringing noises in their ears at the end of the workday, they may be exposed to too much noise.
  3. If employees complain that the sounds of speech or music seem muffled after leaving work, but that their hearing is fairly clear in the morning when they return to work, they have been exposed to noise levels that cause a partial temporary loss of hearing, which can become permanent upon repeated exposure.

Refer to the hazard assessment process below for typical areas of elevated noise.


Do I Need Hearing Protection - Personal Protective Equipment?

Specific types of protection will be required depending on the type and level of noise encountered. EHS will conduct hazard assessments (noise monitoring) of all suspect excessive (hazardous) noise sources to determine the proper personal hearing protection equipment needed.

There are several types of Hearing Protection available. Examples of the more common hearing protection are:

  • Premolded ear plugs: Premolded ear plugs are usually made to fit, by a professional, a specific individual's ears. A snug fit is the most important part of this type of ear plug. Professionally fit ear plugs can be helpful to individuals with irregularly shaped ears. Musician's ear plugs apply to specific music industry professional needs. Special filters let the listener hear music at a safe level without sacrificing quality.
  • Disposable ear plugs: These are usually made of a soft foam material that is compacted and inserted into the ear where it expands to form a snug fit. Once this plug is removed it will further expand to its original shape.
  • Ear muffs: Ear muffs form a acoustic barrier by completely encompassing an individual's ears. Proper fit is affected by the size and shape of the wearer's ears and head.

Please refer to the EHS Website page Hearing Protection and the MU Business Policy and Procedure Manual on Hearing Protection for additional information.


Hazard Assessment (Noise Monitoring) Process

Supervisors should be contacted first if there is an excessive noise complaint. The supervisor will then contact EHS. Hazard assessments (noise monitoring) of all suspect work areas with sound level meters or noise dosimeters will be provided by EHS to determine the appropriate level of protection.

Typical areas of elevated noise include:

  • Activities using lawn mowers, leaf blowers, week trimmers, tractors, snowblowers, and similar items.
  • Rooms containing compressors, fans, emergency generators, and other large mechanical equipment.
  • Machinist shops, wood shops, paint booths, power plants, roof strobic and other fan units, and similar items.
  • Music industry professionals, bands, recordings, and conductors.


Community Noise Process

The acceptability of noise in a given community depends on many factors. It is evaluated according to effect on ambient level and in comparison to professionally recognized performance-type community noise standards. Contact EHS for any community noise concerns or issues.