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.

November 21, 1995

Mr. Richard J. Klaproth
Safety Manager
The Stebbins Engineering and
Manufacturing Company
363 Eastern Boulevard
Watertown, New York 13601

Dear Mr. Klaproth:

This is in response to your March 1, letter requesting an interpretation of the Occupational Safety and Health Administration (OSHA) construction standards for electrical branch circuits.

As you know, the definition of branch circuit is contained in the definition section of Subpart K-Electrical. The definition of a branch circuit is, "the circuit conductors between the final overcurrent device protecting the circuits and the outlet(s)." "Outlet" is defined as "[a] point on the wiring system at which current is taken to supply utilization equipment." The Occupational Safety and Health Review Commission has held that the receptacle end of an extension cord is an "outlet" within the meaning of the electrical standards. Otis Elevator Co., 17 BNA OSHC 1167 (No. 90-2046, 1995).

With regard to whether or not extension cord sets and lighting strings are considered to be branch circuits, please be advised that this equipment is generally considered to be part of the branch circuit wiring for the purposes of 1926.405(a)(2)(ii)(B). This equipment is normally used as temporary branch circuit wiring and serves the same purpose during the construction phase as the permanent branch circuit wiring serves once construction is complete. Extension cord sets must also meet 1926.405(a)(2)(ii)(I) and (a)(2)(ii)(J). Lighting strings must also meet 1926.405(a)(2)(ii)(F), (a)(2)(ii)(I), and (a)(2)(ii)(J).

Flexible cables can be used as temporary feeders or branch circuits. Unless included as an integral part of utilization equipment, these cables must meet either paragraph (b)(2)(ii)(A) or (b)(2)(ii)(B) of 1926.405.

Power supply cords are part of the utilization equipment to which they are attached. They must meet the provisions of 1926.405(a)(2)(ii)(I).

If you have any further questions on this matter, please contact me or Mr. Dale Cavanaugh of my staff at (202) 219-8136.

Thank you for your interest in occupational safety and health.


Roy F. Gurnham, P.E., J.D.
Office of Construction and
Maritime Assistance