OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

January 19, 1982

Mr. Ben F. Ervin
Corporate Safety Enginee
Brutler Manufacturing Company
BMA Tower, Penn Valley Park
Kansas City, Missouri 64141

Dear Mr. Ervin:

Dr. Alice Suter has asked me to respond to your inquiry concerning compliance with the monitoring requirement of the new hearing conservation amendment (29 CFR 1910.95(e)(1)). Please accept my apology for the delay in our response.

The intent of the requirement for workplace noise monitoring is to identify employees who need to be included in the hearing conservation program. Employers have some flexibility in how they achieve this regulatory goal.

Thus, Butler Manufacturing Company may choose to include all workers (regardless of individual noise exposure levels) in the hearing conservation program, as long as all of the other provisions of the standard are followed for each employee.

As your letter indicates, some of these provisions may require some monitoring of the noise levels to assure that workers are adequately protected. For example:

1. Hearing protectors must attenuate employee noise exposure at least to a time-weighted average (TWA) of 90 decibels. (29 CFR 1910.95(m)(2))

2. For employees who have experienced a significant threshold shift, hearing protectors must attenuate employee noise exposures to a TWA of 85 decibels or below. (29 CFR 1910.95(m)(3))

3. Hearing protectors are mandatory for employees who are exposed to a TWA of 85 decibels or greater and who have experienced a significant threshold shift. (29 CFR 1910.95(l)(2)(i))

4. An employee's audiogram record shall include the employee's most recent noise exposure assessment. (29 CFR 1910.95(q)(2)(ii)(f))

We appreciate your bringing this concern to our attention. OSHA is striving to ensure a minimum of interference with the activities of employers, while at the same time ensuring that necessary actions are taken to protect the safety and health of workers. If we can serve you again, we shall be glad to do so.


Glen R. Williamson
Agency Coordinator of Noise Projects