1910.334(b): Opening, Closing and Resetting Circuits Safely
Circuits under load must be opened, reversed or closed only with load-rated switches, circuit breakers or devices designed as disconnects, not fuses, splices or non-load-break connectors except in an emergency. After a protective device trips, the circuit may not be manually reenergized until it is safe; repeated reclosing is prohibited. Overcurrent protection may not be modified beyond 1910.304(e).
Key takeaways
- 1910.334(b) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart S).
- OSHA cited it 20 times in the last 3 years, in 20 inspections, with $50,239 in current penalties.
- Most citations: MI (4), TN (4), CA (2).
- Related part: 1910.334(b)(2) Reclosing circuits after protective device operation (12 citations).
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In this article
What this rule covers
29 CFR 1910.334(b) ("Electric power and lighting circuits") is one requirement inside 1910.334 Use of equipment, an OSHA general industry standard (Part 1910, Subpart S). It includes 3 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
(b) Electric power and lighting circuits — 20 citations
(1) Routine opening and closing of circuits. Load rated switches, circuit breakers, or other devices specifically designed as disconnecting means shall be used for the opening, reversing, or closing of circuits under load conditions. Cable connectors not of the load-break type, fuses, terminal lugs, and cable splice connections may not be used for such purposes, except in an emergency. 8 citations
(2) Reclosing circuits after protective device operation. After a circuit is deenergized by a circuit protective device, the circuit may not be manually reenergized until it has been determined that the equipment and circuit can be safely energized. The repetitive manual reclosing of circuit breakers or reenergizing circuits through replaced fuses is prohibited. Open (b)(2) 12 citations
When it can be determined from the design of the circuit and the overcurrent devices involved that the automatic operation of a device was caused by an overload rather than a fault condition, no examination of the circuit or connected equipment is needed before the circuit is reenergized.
(3) Overcurrent protection modification. Overcurrent protection of circuits and conductors may not be modified, even on a temporary basis, beyond that allowed by § 1910.304(e), the installation safety requirements for overcurrent protection.
Source: eCFR, text current as of 2026-10-15. Read all of 1910.334.
Export the list: 20 inspections cited 1910.334(b) in the last 3 years, with employer, location, penalty and date.
Purple Belt, $59/moWhere and how often it was cited
| Year | Citations |
|---|---|
| 2024 | 8 |
| 2025 | 7 |
| 2026 | 5 |
Top states: MI (4), TN (4), CA (2), WI (1), AZ (1)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| 160596 - PERDUE FOODS LLC | COFIELD, NC | $16,550 |
| HEIDELBERG MATERIALS NORTHEAST LLC | GLEN MILLS, PA | $11,823 |
| ALL TESTING SPECIALISTS, LLC | HARTLAND, WI | $6,742 |
| WOLLASTON ALLOYS, INC. | BRAINTREE, MA | $6,000 |
| STONE DEPOT OF RHODE ISLAND, INC. | CRANSTON, RI | $3,039 |
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A 5-minute crew talk on 1910.334(b), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1910.334(b).
Related parts of this rule
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Frequently asked questions
Can I reset a breaker that keeps tripping?
No. Repetitive manual reclosing of circuit breakers or reenergizing through replaced fuses is prohibited; first determine the circuit can be safely energized.
Can I pull a fuse to break a load?
Fuses, non-load-break cable connectors, terminal lugs and splices may not be used to open circuits under load except in an emergency.
Is an inspection always needed before reclosing?
Not when the circuit design and devices show the trip was caused by an overload rather than a fault.
About this page
Sources
- 29 CFR 1910.334 (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 2026-11-06
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.