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 11, l982

Mr. Peter S. DeFao, Jr.
Senior Staff Industrial Hygienist
Exxon Company, U.S.A.
P.O. Box 222
Linden, New Jersey 07036

Dear Mr. DeFao:

This is in response to your inquiry of December 7, 1981, regarding interpretation of the Hearing Conservation Amendment to OSHA's noise standard, 29 CFR 1910.95.

While it may be more difficult to track the noise exposure of some because of their mobility in their jobs, no employee is to be excluded from the hearing conservation program because of intermittent or variable exposures. In arriving at each employee's exposure, employers may use any approach involving measurements or calculations that are considered appropriate. Compliance with the 8-hour, time-weighted average 85 dB exposure level is determined through the integration of all continuous, intermittent and impulsive sounds between 80 dB and 130 dB.

The use of averages in determining noise exposures may exclude from the program some employees who should be included. In enforcing the standard, OSHA will use monitoring to determine whether employers have failed to include in the hearing conservation program all employees whose exposure equal or exceed a TWA of 85 dB. In addition, since employees covered by the hearing conservation program must be given an annual audiometric test, your present program may not meet this frequency in all cases where audiometric tests are required.

We hope you will find this information helpful. If you have any further questions, please do not hesitate to contact us.


Patrick R. Tyson
Federal Compliance and State Programs