Standard Interpretations - Table of Contents Standard Interpretations - Table of Contents
• Standard Number: 1926; 1926.404; 1926.404(b)(1); 1926.404(b)(1)(i); 1926.404(b)(1)(ii); 1926.404(b)(1)(iii); 1926.32(f)

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

February 7, 2005

Mr. Jeffrey P. Scarpello, Esq.
Executive Director
Penn-Del-Jersey Chapter
National Electrical Contractors Association
1500 Walnut Street
Suite 1630
Philadelphia, PA 19102

Re: Whether the requirements of §1926.404(b)(1) apply to 208-volt branch circuits; whether an electrical subcontractor is required under §1926.404(b)(1) to monitor other on-site subcontractors' compliance with that provision?

Dear Mr. Scarpello:

This is in response to your letter dated September 23, 2004, to the Occupational Safety and Health Administration. You ask about the applicability of §1926.404(b)(1) to 208-volt branch circuits, as well as any responsibility of an electrical subcontractor to monitor other subcontractors' compliance with the provision.

We have paraphrased your questions as follows:

Question (1): Does Part 1926 Subpart K require that all 120-volt, single-phase outlets have ground fault circuit interrupter (GFCI) protection? Also, does Subpart K say that outlets with voltages above 120 volts do not have to be protected from ground faults?

Answer: The answer to both questions is no. Section 1926.404(b)(1)(i) provides:
(b) Branch circuits -- (1) Ground-fault protection
(i) General. The employer shall use either ground fault circuit interrupters as specified in paragraph (b)(1)(ii) of this section or an assured equipment grounding conductor program ["AEGCP"] as specified in paragraph (b)(1)(iii) of this section to protect employees on construction sites. [Emphasis added.] These requirements are in addition to any other requirements for equipment conductors.
Therefore, under paragraph 1926.404(b)(1)(i), the employer is required to provide ground fault protection -- either by the use of ground fault circuit interrupters (GFCIs) or by the use of an assured equipment grounding conductor program. Note that there is no voltage limit to this requirement.

The first option for meeting the requirement that there be ground fault protection is by the use of GFCIs. The requirements for that option are spelled out in paragraph 1926.404(b)(1)(ii):
(ii) Ground-fault circuit interrupters. All 120-volt, single-phase, 15- and 20- ampere receptacle outlets on construction sites, which are not part of the permanent wiring of the building or structure and which are in use by employees, shall have approved ground-fault circuit interrupters for personnel protection.
* * *
The other option for meeting the requirement that there be ground fault protection is by the use of an assured equipment grounding conductor program. The requirements for that option are spelled out in paragraph 1926.404(b)(1)(iii). While there are several applicable provisions of paragraph 1926.404(b)(1)(iii), we note two in particular:
(iii) Assured equipment grounding conductor program. The employer shall establish and implement an assured equipment grounding conductor program on construction sites covering all cord sets, receptacles which are not a part of the building or structure, and equipment connected by cord and plug which are available for use or used by employees.
* * *
(B) The employer shall designate one or more competent persons (as defined in §1926.32(f)) to implement the program. [Emphasis added.]
* * *
(F) The employer shall not make available or permit the use by employees of any equipment which has not met the requirements of this paragraph (b)(1)(iii) of this section. [Emphasis added.]
In your letter you focus on the part of paragraph 1926.404(b)(1)(ii) -- the GFCI option -- that refers to 120-volt outlets being protected by GFCIs. That part of paragraph 1926.404(b)(1)(ii) means that the GFCI option, as written, was available only for 120-volt, single-phase, 15- and 20-ampere receptacle outlets. Because there is no voltage limit to the requirement in 1926.404(b)(1)(i) to provide ground fault protection by one of the two listed options (GFCI or assured grounding program), as originally written the standard in effect required that outlets over 120 V had to be protected by an assured grounding program.

However, as we explained in our May 15, 2002, Mercuris letter, the 120-V limitation for use of the GFCI option was put in the standard only because GFCIs for higher voltages were generally unavailable at the time the standard was promulgated. Since then GFCIs have become available for higher voltages. So, as we stated in Mercuris, use of a GFCI to protect a circuit with a voltage higher than 120 volts would be acceptable to meet the paragraph 1926.404(b)(1)(i) ground fault protection requirement. It would be considered only a de minimis violation
1 as long as the GFCI was designed to protect a circuit of that voltage.

In sum, under §1926.404(b)(1)(i), employers must provide ground fault protection. This requirement is not limited to 120-V outlets -- it applies to outlets with higher voltages as well. Employers have two options for meeting this requirement -- by using GFCIs designed for the particular voltage or by implementing an assured equipment grounding conductor program.

Question (2): Scenario A: A general contractor brings in an electrical subcontractor to install temporary electrical service at a construction site. The electrical sub properly installs a service panel. Each outlet in the service panel is grounded. There is no contractual requirement that the electrical sub maintain assured grounding programs.

Scenario B: Same as Scenario A, except that the electrical subcontractor properly installs GFCI protection for each outlet. There is no contractual requirement that the electrical sub maintain the GFCIs.

In Scenarios A and B, is the electrical subcontractor required to monitor the compliance of other on-site subcontractors with the ground fault protection provisions of §1926.404(b)(1)?

Answer: No. As noted above, §1926.404(b)(1)(i) provides that the "employer" is required to use either a GFCI or an assured equipment grounding conductor program for ground fault protection. The Preamble to this rule (volume 41 of the Federal Register, page 55696) discussed the rationale behind offering the alternative methods of compliance under §1926.440(h)(1).
* * * the use of assured equipment grounding conductor programs on construction sites can be as effective as ... the use of GFCI's.
* * * an employer may choose one method of protection or the other on the basis of several factors. The individual employer may choose on the basis of cost; if his local jurisdiction already requires GFCI's, he may choose GFCI's; if he is one employer of many on a construction site, the availability of alternatives gives him flexibility to coordinate compliance. [Emphasis added.]
This reflects an intent that the term "employer," as used in §1926.404(b)(1)(i) of the ground fault provision, when applied in the context of a construction site with multiple employers, refers to each of the employers/subcontractors with employees exposed to the hazard. Thus, each employer/subcontractor on the site that has exposed employees is obligated to ensure that one of the options is in "use."

In sum, in Scenarios A and B, absent any additional factors,
3 the electrical subcontractor would not be responsible for monitoring the compliance of other subcontractors at the site with §1926.404(b)(1).

If you need additional information, please contact us by fax (202-693-1689) at: U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance, fax # 202-693-1689. You can also contact us at the above office, Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210, although there will be a delay in our receiving correspondence by mail.


Russell B. Swanson, Director
Directorate of Construction

1 Under OSHA's de minimis policy, de minimis violations are those which have no direct or immediate relationship to safety or health. Consequently, no citation is issued.
[ back to text ]

2Section 1926.440(h) was the predecessor provision to §1926.404(b)(1). [ back to text ]

3For example, in A/C Electric Company v. OSHRC, 956 F.2d 530 (6th Cir. 1991), the Circuit Court upheld a Review Commission decision holding that a subcontractor violated §1926.404(b)(1)(ii) where it was contractually responsible for maintaining the temporary service notwithstanding that it neither caused the hazardous condition nor had employees exposed to them. This case and several others emphasized that the subcontractor was both "in control" of an area and contractually responsible for its maintenance. [ back to text ]

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