Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

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

September 24, 1987


FROM:            THOMAS J. SHEPICH, Director
                 Directorate of Compliance Programs

THRU:            LEO CAREY, Director
                 Office of Field Programs

SUBJECT:         Clarification of 29 CFR 1926.403(a)

In the revised Subpart K, Electrical Standards for Construction the language of the requirement for approval in 1926.403(a) differs from the wording given in Subpart S, Electrical Standards for General Industry, 1910.303(a). However, while different language was used in Subpart K, no difference in the implementation of the requirement was intended.

In both standards, Subpart K and Subpart S, the definition of "approved" leads to the definition of "acceptable," which provides for acceptance of electric equipment based in testing by a laboratory (among other means of acceptance). The Subpart K requirement for approval is not intended to expand equipment testing beyond what has taken place under Subpart S.

In determining the acceptability of electric equipment that is of a type that has not historically been tested by a "qualified electrical testing laboratory," OSHA compliance staff must consider the decisions of local authorities responsible for enforcing the National Electrical Code.