February 4, 1992
MEMORANDUM FOR: BYRON R. CHADWICK
THROUGH: LEO CAREY, DIRECTOR
OFFICE OF FIELD PROGRAMS
FROM: PATRICIA K. CLARK, DIRECTOR
DIRECTORATE OF COMPLIANCE PROGRAMS
SUBJECT: Magna Electrical Construction Co., Inc. Letter
Requesting Ground Fault Circuit Interrupter Information
This is in response to your November 18 memorandum forwarding the Magna
Electrical Construction Company's request for information on OSHA
requirements for testing ground fault circuit interrupters (GFCIs) at
construction sites. I apologize for the delay in responding to your inquiry.
Section 1926.404(b)(1) does not require GFCIs to be tested. However,
1926.20(b)(2) does require the frequent and regular inspections of equipment.
The instructions included with the devices indicate that they should be
tested monthly. If an employer can demonstrate, for example, by means of
logs or procedures, that he or she tests GFCIs monthly and promptly replaces
those found defective, then a serious citation may not be appropriate for
defective GFCIs found upon inspection, provided the faulty devices are
In regard to Magna's remaining two questions concerning the proper
procedures for testing GFCIs, I have attached the Electrical/Electronic
Technical Note 91-1 which outlines the acceptable test procedure.