1910.305(b)(1)(ii): Close Unused Openings in Electrical Boxes
Employers must make sure unused openings in electrical cabinets, boxes and fittings are effectively closed. Open holes can let fingers, tools or debris reach live parts inside, so every unused opening must be properly sealed. This applies to cabinets, boxes and fittings throughout the electrical installation.
Key takeaways
- 1910.305(b)(1)(ii) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart S).
- OSHA cited it 1,058 times in the last 3 years, in 1,057 inspections, with $1,531,594 in current penalties.
- 3 deaths are linked to inspections that cited this rule.
- Most citations: TN (162), MD (106), VA (61).
- Related part: 1910.305(b) Cabinets, boxes, and fittings (2,745 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1910.305(b)(1)(ii) is one requirement inside 1910.305 Wiring methods, components, and equipment for general use, an OSHA general industry standard (Part 1910, Subpart S). 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) Unused openings in cabinets, boxes, and fittings shall be effectively closed. 1,058 citations
Source: eCFR, text current as of 2026-10-15. Read all of 1910.305.
Injuries linked to this rule
3 deaths are linked to inspections where OSHA cited 1910.305(b)(1)(ii).
At 5:00 p.m. on September 24, 2024, Employee #1 was checking trusses in preparation to feed them into a finish press. The employee had two trusses side by side and was preparing to send them through the rollers when one of the trusses pushed the…
Full case list with employer, penalty, filters and download is part of OSHA Data (Purple Belt).
Unlock with Purple BeltWhere and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 64 |
| 2024 | 358 |
| 2025 | 401 |
| 2026 | 235 |
Top states: TN (162), MD (106), VA (61), MI (59), HI (57)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| DCR | BAYAMON, PR | $35,000 |
| NUCO FOODS, LLC | ELIZABETHTOWN, PA | $27,308 |
| HOME DEPOT U.S.A., INC. | HONOLULU, HI | $23,646 |
| ALLIED TUBE & CONDUIT CORPORATION | HARVEY, IL | $16,550 |
| THE GOODYEAR TIRE & RUBBER COMPANY | DANVILLE, VA | $15,875 |
Free toolbox talk
A 5-minute crew talk on 1910.305(b)(1)(ii), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1910.305(b)(1)(ii).
Related parts of this rule
- 1910.305(b) Cabinets, boxes, and fittings 2,745 citations
- 1910.305(b)(2) Covers and canopies 1,373 citations
- 1910.305(b)(2)(i) 1,349 citations
- 1910.305(b)(1) Conductors entering boxes, cabinets, or fittings 1,314 citations
- 1910.305(b)(1)(i) 202 citations
- 1910.305(b)(3) Pull and junction boxes for systems over 600 volts, nominal 58 citations
- 1910.305(b)(3)(ii) 46 citations
- 1910.305(b)(1)(iii) 21 citations
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
What equipment does this rule cover?
Cabinets, boxes and fittings in electrical installations.
What counts as an unused opening?
Any hole in the enclosure that is not being used, such as a missing knockout or an empty conduit hole.
Why are open holes a hazard?
They can let a person, tool or debris contact energized parts inside the enclosure.
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 2026-10-20
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.