1926.404(b)(1)(ii): GFCI Protection on Construction Sites
All 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites that are not part of the building's permanent wiring and are used by employees must have approved ground-fault circuit interrupters. Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated not more than 5kW, with conductors insulated from the frame and other grounded surfaces, do not need GFCIs.
Key takeaways
- 1926.404(b)(1)(ii) is part of OSHA's construction standards (29 CFR Part 1926, Subpart K).
- OSHA cited it 50 times in the last 3 years, in 50 inspections, with $77,676 in current penalties.
- 1 death is linked to inspections that cited this rule.
- Most citations: PR (12), IN (9), IL (5).
- Related part: 1926.404(b) Branch circuits (138 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1926.404(b)(1)(ii) ("Ground-fault circuit interrupters") is one requirement inside 1926.404 Wiring design and protection, an OSHA construction standard (Part 1926, Subpart K). The official text below is copied word for word from the Electronic Code of Federal Regulations (eCFR). The numbers, injury cases and training on this page show how OSHA enforces it on real job sites.
Official text
(ii) Ground-fault circuit interrupters. All 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites, which are not a 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. Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated not more than 5kW, where the circuit conductors of the generator are insulated from the generator frame and all other grounded surfaces, need not be protected with ground-fault circuit interrupters. 50 citations
Source: eCFR, text current as of 2026-10-15. Read all of 1926.404.
Injuries linked to this rule
1 death is linked to inspections where OSHA cited 1926.404(b)(1)(ii).
At 11:00 a.m. on July 28, 2024, an employee working as a construction laborer for a masonry contractor was core drilling a concrete floor. The employee's coredrill came into contact with electrical wiring. The employee was electrocuted and died.
Where and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 2 |
| 2024 | 24 |
| 2025 | 12 |
| 2026 | 12 |
Top states: PR (12), IN (9), IL (5), DC (4), VA (4)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| DEL VALLE GROUP, LLC. | SAN JUAN, PR | $11,333 |
| FIRST NATIONWIDE CONSTRUCTION CORP | WABAN, MA | $5,323 |
| ORTIZ CONCRETE, CUTTING & CORE DRILLING LLC | WEEHAWKEN, NJ | $4,965 |
| COTTON INTERNATIONAL INC. | PONCE, PR | $4,613 |
| HAMILTON PACIFIC CHAMBERLAIN, LLC | BALTIMORE, MD | $3,724 |
Free toolbox talk
A 5-minute crew talk on 1926.404(b)(1)(ii), plus alerts when this rule changes. Free.
OSHA interpretation letters
- Application of 1926.404(b)(1) to 208-volt branch circuits; requirement for electrical subcontractor under 1926.404(b)(1) to provide ground-fault circuit interrupters on circuits used by other subcontractors (2005-03-22)
- Requirements of 1926.404(b)(1) application to 208-volt branch circuits; electrical subcontractor requirements under 1926.404(b)(1) to monitor other on-site subcontractors. (2005-02-07)
- CSHO use of external GFCI testers to enforce 29 CFR 1926.404(b)(1) (2003-07-09)
- Use of approved GFCI's that do not have open-neutral protection. (2003-07-07)
- Ground fault protection requirements for 120-volt and/or 240-volt circuits. (2002-05-15)
- GFCI and coverplate requirements in construction;use of fall arrest systems and scaffolding. (1999-10-14)
- Use of flexible cords for connection of appliances; scaffold base plates. (1998-07-20)
- Proper equipment for testing ground-fault circuit interrupters (GFCIs). (1993-12-09)
Related parts of this rule
- 1926.404(b) Branch circuits 138 citations
- 1926.404(b)(1) Ground-fault protection 137 citations
- 1926.404(b)(1)(iii)(C) 42 citations
- 1926.404(b)(1)(iii) Assured equipment grounding conductor program 42 citations
- 1926.404(b)(1)(i) General 41 citations
- 1926.404(b)(2) Outlet devices 1 citations
- 1926.404(b)(1)(iii)(G)
- 1926.404(b)(1)(iii)(E)
- 1926.404(b)(1)(iii)(D)
Get your crew competent
Trainers on Black Belt Safety: Marc Harvey, Dana Reyes
Trainers and suppliers: feature your business on this rule for $25/month.
Frequently asked questions
Which outlets need GFCI protection on a construction site?
All 120-volt, single-phase, 15- and 20-ampere receptacles not part of permanent wiring and in use by employees.
Do small generators need GFCIs?
Receptacles on a two-wire, single-phase generator rated not more than 5kW, with conductors insulated from the frame and grounded surfaces, need not have GFCIs.
What does a GFCI protect?
It is required for personnel protection.
About this page
Sources
- 29 CFR 1926.404 (eCFR), text current as of 2026-10-15
- U.S. Department of Labor enforcement data: OSHA inspections, citations and accident records, copied nightly; data as of 2026-10-19
3-year window. Federal OSHA only; state-plan rules are not counted. Plain-language text is a summary, not legal advice; the official text controls. Black Belt Safety is not part of OSHA or the Department of Labor.