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.

Dec 17, 1976

Mr. Joseph F. Gerling
Extension Safety Specialist
Cooperative Extension
Service Division of Agriculture
Oklahoma State University
Stillwater, Oklahoma 74074

Dear Mr Gerling:

This is in response to your letter of September 2, 1976, addressed to the OSHA Tulsa Area Office, which was forwarded to the National Office for reply. Your letter was in regard to 29 CFR 1928.57(c)(5)(ii), regarding "Electrical Disconnect Means" as they relate to center pivot irrigation systems.

The primary purpose of an electrical disconnect means is to prevent someone from inadvertently starting a piece of equipment while another employee is in the process of doing maintenance or making repairs, thereby exposing that employee to the possibility of injuries caused by moving or rotating parts, and/or energized circuits.

As discussed with you over the telephone recently by a member of my staff, the equipment now in use could be brought in compliance with the standard by the installation of a single electrical lockout system under the exclusive control of the employee doing the actual maintenance or repairs. The lockout system, along with the posting of the required signs on the individual towers, should provide the safe work conditions for which the standard was intended.

Thank you for you concern and interest in occupational and safety and health.

If I may be of any further assistance, please to not hesitate to contact me.


John K. Barto, Chief
Occupational Safety Programming