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.

May 13, 2004

Mr. Kent Davis
Arc Electric, Inc
500 Woodlake Dr. Suite 105
Chesapeake, VA 23320

Re: Maximum allowable distance between supports for temporary wiring; 1926.405.

Dear Mr. Davis:

This is in response to your letter dated March 10, 2004, to the Occupational Safety and Health Administration (OSHA), asking for clarification of OSHA's construction standards for temporarily secured non-metallic sheathed wiring.

We have paraphrased your questions as follows:

Question (1): We use Romex (a non-metallic sheathed cable) when installing temporary wiring. Title 29 CFR 1926.405(a)(2) (Subpart K, Electrical) does not specifically state the minimum distance at which our wiring must be secured. Would securing our temporary wiring every 10 feet violate any provision within Subpart K?


"Romex" is the trade name of a specific type of cable. The electrical classification for Romex-style cable is non-metallic sheath cable. The 1984 National Electrical Code stated that, in additional to code sections that specifically address temporary wiring, all requirements of the 1984 Code for permanent wiring also apply to temporary wiring. One of the requirements for permanent wiring, and thus for temporary wiring, was the need for adequate support. Article 336-18 stated that cable must be secured in place at intervals not exceeding 4.5 feet (1.37 m) and within 12 inches (305 mm) from every cabinet, box, or fitting.

In the 1999 NEC
1, a change was made to the temporary wiring section. Article 305-4(j) was added and states:

Cable assemblies and flexible cords and cables shallbe supported in place at intervals that ensure they will be protected from physical damage. ...

This passage was added to clarify that temporary wiring does not have to be supported in the same manner afforded permanent wiring installations.

Section 1926.402 states in a note that:

If the electrical installation is made in accordance with the National Electrical Code ANSI/NFPA 70-1984 ... it will be deemed to be in compliance with §§1926.403 through 1926.408, except for §§1926.404(b)(1) and 1926.405(a)(2)(ii)(E), (F), (G) and (J).

This provision was drafted to allow employers that meet the electrical installation standards in the 1984 National Electric Code (NEC) to be deemed in compliance with the applicable sections of §§1926.403-1926.408 of Subpart K.

There is no provision in the text of Part 1926 Subpart K that specifies a particular maximum distance between supports for temporary wiring. However, 29 CFR 1926.403(b)(1) states in part:

The employer shall ensure that electrical equipment is free from recognized hazards that are likely to cause death or serious physical harm to employees. ...



Temporary cable must be secured at intervals that will ensure that the cable is sufficiently protected from contact with people, equipment, construction materials, or other such items that could cause serious harm to employees if they strike or damage the cables. In your situation, if supporting the cable at 10-foot intervals would protect it from this type of contact, then the requirements of the standard with respect to spacing would be met.

If you need additional information, please do not hesitate to contact us by fax at: U.S. Department of Labor, OSHA, Directorate of Construction, Office of Construction Standards and Guidance, fax # 202-693-1689. You can also contact us by mail at the above office, Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210, although there will be a delay in our receiving correspondence by mail.


Russell B. Swanson, Director
Directorate of Construction



1 This change has been maintained in the 2002 National Electrical Code. [ back to text ]