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.

June 9, 1987

Robert A. Dobie, M.D.
Subcommittee, Medical Aspects of Noise
University of Washington
Seattle, Washington 98195

Dear Dr. Dobie:

This is in response to your letter of February 27 addressed to Mr. John B. Miles, Jr., concerning the requirement for instituting engineering and administrative controls for noise.

The standard for occupational exposure to noise requires employers to utilize feasible administrative or engineering controls for noise when any employee exposures during a workday exceed the equivalent of a constant sound pressure level of 90 dBA for eight hours. This basic requirement can only be changed through rulemaking.

What the Occupational Safety and Health Administration (OSHA) has done is provide our compliance officers with guidelines for executing a U.S. Court of Appeals decision concerning the feasibility of utilizing engineering and administrative controls for noise.

In Donovan v. Castle and Cooks Foods and the Occupational Safety and Health Review Commission, the U.S. Court of Appeals for the Ninth Circuit held that implementation of engineering or administrative controls could not be required without comparing the relative costs and effectiveness of this approach with the alternative approach of using personal protective equipment.

OSHA's current policy for enforcing the use of engineering and administrative controls for noise is contained in the Agency's Field Operations Manual and the appendix to OSHA Instruction CPL 2-2.35A. A copy of this information is enclosed.

Thank you for contacting OSHA. If we may assist you again in the future, we shall be glad to do so.


Leo Carey, Director
Directorate of Field Operations