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.

January 28, 1994

Mr. Paul Weiss
Regional Sales Manager
Wyco Tool Company
P.O. Box 185
Augusta, WV 26704

Dear Mr. Weiss:

This is in response to your December 7 letter requesting an interpretation of Occupational Safety and Health Administration (OSHA) standards addressing hand tools used in construction.

With regard to whether all electric tools need to be tested by a qualified national testing laboratory and be listed and labeled, please be advised that 29 CFR 1926.403(a) requires all electric equipment, including double insulated and grounded hand tools, to be approved. OSHA defines "approved" at 1926.449 as being accepted, or certified, or listed, or labeled, or otherwise determined to be safe by a qualified testing laboratory.

With regard to the provisions addressing the grounding of electric hand tools, please be advised that 1926.302(a) requires that an electric hand tool be either double insulated or be equipped with a grounding conductor with a three-prong plug in accordance with Subpart K of part 1926. Therefore, a non- grounded, double-insulated electric hand tool with associated two-prong plug which has been listed by a nationally recognized testing laboratory would comply with 1926.302(a) and 1926.403(a).

If we can be of any further assistance, please contact me or Mr. Dale Cavanaugh at (202) 219-8136.


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

December 7, 1993

Mr. Dale R. Cavanaugh, P.E.
Occupational Safety and Health
Division of Construction Compliance
200 Constitution Ave. Room N361
Washington, D.C. 20210

Dear Mr. Cavanaugh,

Thanks for giving me your time to discuss the safety of electric tools used in construction. As we discussed, I would appreciate if you would clarify OSHA regulations applicable to electric tools as contained in 29 CFR 1926.302, 403(a), and 29 CFR 1926.449.

It is my understanding that all electric tools, both grounded and double insulated, must be tested by a qualified national testing laboratory, be labeled and listed, to ensure the safety of the tool and to be in compliance with OSHA standards. Is my understanding correct?

Am I correct that the use of a non-grounded two prong plug, used on a double-insulated tool, which has been listed by a qualified national testing laboratory, fully complies with OSHA standards.

Mr. Cavanaugh, thanks again for helping to clarify these issues.


Paul Weiss
Regional Sales Manager
Wyco Tool Company