1926.404(f)(3): Portable and vehicle-mounted generators
Key takeaways
- 1926.404(f)(3) is part of OSHA's construction standards (29 CFR Part 1926, Subpart K).
- Related part: 1926.404(f) Grounding (241 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1926.404(f)(3) ("Portable and vehicle-mounted generators") is one requirement inside 1926.404 Wiring design and protection, an OSHA construction standard (Part 1926, Subpart K). It includes 9 sub-paragraphs. 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
(3) Portable and vehicle-mounted generators —
(i) Portable generators. Under the following conditions, the frame of a portable generator need not be grounded and may serve as the grounding electrode for a system supplied by the generator: Open (f)(3)(i)
(A) The generator supplies only equipment mounted on the generator and/or cord- and plug-connected equipment through receptacles mounted on the generator, and
(B) The noncurrent-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.
(ii) Vehicle-mounted generators. Under the following conditions the frame of a vehicle may serve as the grounding electrode for a system supplied by a generator located on the vehicle:
(A) The frame of the generator is bonded to the vehicle frame, and
(B) The generator supplies only equipment located on the vehicle and/or cord- and plug-connected equipment through receptacles mounted on the vehicle or on the generator, and
(C) The noncurrent-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame, and
(D) The system complies with all other provisions of this section.
(iii) Neutral conductor bonding. A neutral conductor shall be bonded to the generator frame if the generator is a component of a separately derived system. No other conductor need be bonded to the generator frame.
Source: eCFR, text current as of 2026-10-15. Read all of 1926.404.
Free toolbox talk
A 5-minute crew talk on 1926.404(f)(3), plus alerts when this rule changes. Free.
OSHA interpretation letters
- Repair requirements for the cord plug (attachment plug) of double-insulated tools. (2003-05-19)
- Wiring, Extension Cords and Grounding. (1993-09-03)
Related parts of this rule
- 1926.404(f) Grounding 241 citations
- 1926.404(f)(6) Grounding path 234 citations
- 1926.404(f)(7) Supports, enclosures, and equipment to be grounded 4 citations
- 1926.404(f)(7)(iv) Equipment connected by cord and plug 3 citations
- 1926.404(f)(1)(iv) AC systems, 50 volts to 1000 volts 2 citations
- 1926.404(f)(1) Systems to be grounded 2 citations
- 1926.404(f)(7)(i) Supports and enclosures for conductors
- 1926.404(f)(3)(i) Portable generators
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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
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.