1910.305(c): Electrical Switch Requirements
Employers must install knife switches so gravity will not close them, with locking devices where required to keep blades open, and connect switches so blades and load terminals are de-energized when open, except where backfeed is possible and a permanent warning sign is posted. Snap switches in boxes need faceplates that completely cover the opening and seat against the surface, and snap switches must be effectively grounded.
Key takeaways
- 1910.305(c) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart S).
- OSHA cited it 121 times in the last 3 years, in 121 inspections, with $173,933 in current penalties.
- Most citations: PR (14), MI (12), OR (10).
- Related part: 1910.305(c)(4) Faceplates for flush-mounted snap switches (121 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1910.305(c) ("Switches") is one requirement inside 1910.305 Wiring methods, components, and equipment for general use, an OSHA general industry standard (Part 1910, Subpart S). It includes 7 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
(c) Switches — 121 citations
(1) Single-throw knife switches. Single-throw knife switches shall be so placed that gravity will not tend to close them. Single-throw knife switches approved for use in the inverted position shall be provided with a locking device that will ensure that the blades remain in the open position when so set.
(2) Double-throw knife switches. Double-throw knife switches may be mounted so that the throw will be either vertical or horizontal. However, if the throw is vertical, a locking device shall be provided to ensure that the blades remain in the open position when so set.
(3) Connection of switches.
(i) Single-throw knife switches and switches with butt contacts shall be connected so that the blades are deenergized when the switch is in the open position.
(ii) Single-throw knife switches, molded-case switches, switches with butt contacts, and circuit breakers used as switches shall be connected so that the terminals supplying the load are deenergized when the switch is in the open position. However, blades and terminals supplying the load of a switch may be energized when the switch is in the open position where the switch is connected to circuits or equipment inherently capable of providing a backfeed source of power. For such installations, a permanent sign shall be installed on the switch enclosure or immediately adjacent to open switches that read, “WARNING—LOAD SIDE TERMINALS MAY BE ENERGIZED BY BACKFEED.”
(4) Faceplates for flush-mounted snap switches. Snap switches mounted in boxes shall have faceplates installed so as to completely cover the opening and seat against the finished surface. Open (c)(4) 121 citations
(5) Grounding. Snap switches, including dimmer switches, shall be effectively grounded and shall provide a means to ground metal faceplates, whether or not a metal faceplate is installed. However, if no grounding means exists within the snap-switch enclosure, or where the wiring method does not include or provide an equipment ground, a snap switch without a grounding connection is permitted for replacement purposes only. Such snap switches shall be provided with a faceplate of nonconducting, noncombustible material if they are located within reach of conducting floors or other conducting surfaces.
Source: eCFR, text current as of 2026-10-15. Read all of 1910.305.
Where and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 10 |
| 2024 | 52 |
| 2025 | 32 |
| 2026 | 27 |
Top states: PR (14), MI (12), OR (10), VA (8), NJ (8)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| THE GOODYEAR TIRE & RUBBER COMPANY | DANVILLE, VA | $13,415 |
| NATIONAL VISION, INC. | LINCOLN, NE | $8,296 |
| WALMART, INC. | NEW CASTLE, DE | $7,604 |
| DE | PATILLAS, PR | $7,093 |
| AEP - CUARTEL DE DISTRITO DE MANAT? | MANATI, PR | $7,000 |
Free toolbox talk
A 5-minute crew talk on 1910.305(c), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1910.305(c).
Related parts of this rule
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Frequently asked questions
How must single-throw knife switches be mounted?
So gravity will not tend to close them; those approved for inverted use need a locking device to keep the blades open.
What sign is needed where backfeed is possible?
A permanent sign reading "WARNING-LOAD SIDE TERMINALS MAY BE ENERGIZED BY BACKFEED" on or next to the switch.
Do switch faceplates have to fit flush?
Yes. Faceplates must completely cover the opening and seat against the finished surface.
About this page
Sources
- 29 CFR 1910.305 (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 2026-10-21
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.