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 http://www.osha.gov.

July 20, 1998

Donald Kriesel
Safety Engineer
Manhattan Construction
1400 N. MacGregor
Houston, Texas 77030

RE: 1926.404(a)(2); 1926.404(b)(1)(ii); 1926.405(g); 1926.451(c)(2); scaffold base plates; electrical box fan.

Dear Mr. Kriesel:

This is in response to your letter dated June 27 to the Occupational Safety and Health Administration (OSHA) in which you asked whether an electrical box fan (residential type) could be used on a construction site if equipped with a flat cord. You also questioned the practice of using a scaffold screw jack without a base plate.

Residential type electrical box fans may be used on construction sites if properly maintained and used. OSHA's electrical standard which covers wiring methods, components and equipment for general use has a section that addresses flexible cords and cables, 29 CFR 1926.405(g). This section lists the suitable conditions in which cords and cables can be used; paragraph (g)(1)(i)(C) specifically mentions "appliances." However, please reference paragraph (g)(1)(iii) for a list of prohibited uses. Obviously, the employer should inspect the surrounding area and eliminate any potential accidental contact and tripping hazards that the unit and its installation may have created. In addition, ensure that the box fan has a cord cap that is properly polarized to eliminate reverse polarity, as stated in §1926.404(a)(2), and should the unit be connected to any temporary electrical service, such as an extension cord, then the ground fault circuit interrupter provisions found in §1926.404(b)(1)(ii) would apply.

OSHA's new scaffold standard, which became effective November 29, 1996, contains criteria for supported scaffolds. Section 1926.451(c)(2) specifies that, "[s]upported scaffold poles, legs, posts, frames, and uprights shall bear on base plates and mud sills or other adequate firm foundation." Placing a scaffold screw jack directly onto a surface, such as a 2 x 10 plank, without a base plate would not sufficiently distribute the weight of the scaffold load and could cause the scaffold to shift and collapse.

If you require further assistance, please do not hesitate to contact us again by writing to: OSHA-Directorate of Construction, Office of Construction Standards and Compliance Assistance, Room N3621, 200 Constitution Avenue, N. W., Washington, D.C. 20210.


Russell B. Swanson, Director
Directorate of Construction