Safety and health newsletter for the Oregon construction industry

February 14, 2013


Questions and answers about electrical cords and temporary power sources

GFCI protection

Is GFCI protection required for temporary power sources? Oregon OSHA's construction rule on branch circuits, 437-003-0404(2), requires GFCI protection for employees working from temporary power sources, using 125-volt, single-phase, 15-, 20-, or 30-ampere receptacles. This requirement applies to all tools and equipment connected to temporary power sources. If a permanently wired receptacle (not equipped with GFCI protection) is used for temporary electric power, GFCI protection must also be available.

For receptacles with more than 125 volts, single-phase, or more than 30-amp capacity, GFCI protection or an assured equipment grounding conductor program is required [See 437-003-0404(3)].

Is GFCI protection required at the user end of the circuit? GFCI protection can be anywhere on the circuit as long as it protects the worker.

How do I know if a GFCI is defective? The best way to determine if a GFCI is defective is to test it with a polarity-checking tool that has a built-in milliamp indicator. If the GFCI trips out at four to six milliamps, it's working; if it trips out below four milliamps, it's defective and must be replaced.

Are electrical cord inspections required? Daily inspections of extension cords and plug-connected equipment are required only as part of an assured equipment grounding conductor program. However, employers are required to ensure that electrical equipment does not have hazards that are likely to cause death or serious physical harm to their employees. So, regular inspections of electrical cords are certainly worth the effort. See 1926.403, General Requirements [Subdivision 3/K].

Does Oregon OSHA have a list of approved colors for identifying electrical cords and equipment? No. Color-coding is an option for identifying cords but there are no approved colors. Employers can use their own methods for identifying cords and equipment as long as other users understand them.


Reprinting, excerpting, or plagiarizing any part of this publication is fine with us!

But remember: the information in this newsletter is intended to highlight safe work practices, but it does not replace Oregon OSHA workplace safety and health rules.

For information about Oregon OSHA services and answers to technical questions, call (503) 378-3272 or toll-free within Oregon, (800) 922-2689.