Hearing conservation program

Hearing conservation programs are designed to prevent noise induced hearing loss. A written hearing conservation program is required by the Occupational Safety and Health Administration (OSHA) "whenever employee noise exposures equal or exceed an 8-hour time-weighted average sound level (TWA) of 85 decibels measured on the A scale (slow response) or, equivalently, a dose of fifty percent." This 8-hour time-weighted average is known as an exposure action value. While the Mine Safety and Health Administration (MSHA) also requires a hearing conservation program, MSHA does not require a written hearing conservation program. MSHA's hearing conservation program requirement can be found in 30 CFR § 62.150, and requires has almost the same exact requirements as the OSHA hearing conservation program requirements. Therefore, only the OSHA standard 29 CFR 1910.95 will be discussed in detail.

The OSHA standard contains a series of program requirements.

A sound survey is often completed to determine areas of potential high noise exposure. This type of survey is normally completed using a sound level meter (SLM). There are three types of sound level meters. Type 0 is precision instrument normally used in laboratories. A type 1 is for precision measurements taken in the field. Type 2 sound level meters are less precise than type 1 and are often used to take all-purpose sound level measurements. Noise monitoring is generally completed using a noise dosimeter that integrates "all continuous, intermittent and impulsive sound levels" to determine a person's noise exposure level.

Surveys must be repeated when there are significant changes in machinery and/or processes that would affect the noise level.

Engineering controls and administrative controls are the preferred method to prevent noise exposure. Normally, they do not require personal protective equipment and therefore are normally more protective. However, it is not always feasible to use administrative and engineering controls as the only ways to prevent noise over-exposure. The key is to maintain an 8-hour time-weighted average of less than 85 dBA so that personal protective equipment is not required. On October 19, 2010, the US Department of Labour proposed that the term "feasible" be interpreted as that which is capable of being done, thus enhancing OSHA's ability to enforce this aspect of the standard.

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