1910.304(b)(4): Outlet Device Ratings
Employers must make sure outlet devices have an ampere rating not less than the load they serve. On branch circuits over 20 amps, lampholders must be heavy-duty, and receptacles must meet rating rules: a single receptacle on its own circuit must be rated at least the circuit rating, and receptacles on multi-outlet circuits must follow Tables S-4 and S-5.
Key takeaways
- 1910.304(b)(4) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart S).
- OSHA cited it 137 times in the last 3 years, in 136 inspections, with $181,351 in current penalties.
- Most citations: MN (43), TN (43), NJ (17).
- Related part: 1910.304(b) Branch circuits (279 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1910.304(b)(4) ("Outlet devices") is one requirement inside 1910.304 Wiring design and protection, an OSHA general industry standard (Part 1910, Subpart S). It includes 5 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
(4) Outlet devices. Outlet devices shall have an ampere rating not less than the load to be served and shall comply with the following provisions: 137 citations
(i) Where connected to a branch circuit having a rating in excess of 20 amperes, lampholders shall be of the heavy-duty type. A heavy-duty lampholder shall have a rating of not less than 660 watts if of the admedium type and not less than 750 watts if of any other type; and
(ii) Receptacle outlets shall comply with the following provisions: Open (b)(4)(ii) 70 citations
(A) A single receptacle installed on an individual branch circuit shall have an ampere rating of not less than that of the branch circuit;
(B) Where connected to a branch circuit supplying two or more receptacles or outlets, a receptacle may not supply a total cord- and plug-connected load in excess of the maximum specified in Table S-4; and Open (b)(4)(ii)(b) 70 citations
(C) Where connected to a branch circuit supplying two or more receptacles or outlets, receptacle ratings shall conform to the values listed in Table S-5; or, where larger than 50 amperes, the receptacle rating may not be less than the branch-circuit rating. However, receptacles of cord- and plug-connected arc welders may have ampere ratings not less than the minimum branch-circuit conductor ampacity.
Source: eCFR, text current as of 2026-10-15. Read all of 1910.304.
Where and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 7 |
| 2024 | 60 |
| 2025 | 41 |
| 2026 | 29 |
Top states: MN (43), TN (43), NJ (17), CT (12), NV (10)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| CLASSIC FLOORS & INTERIORS, LLC | LAS VEGAS, NV | $11,524 |
| IGNITE TEEN TREATMENT LLC | LAS VEGAS, NV | $10,046 |
| HACKETTSTOWN PUBLIC SCHOOL DISTRICT | HACKETTSTOWN, NJ | $7,000 |
| HACKETTSTOWN PUBLIC SCHOOLS | HACKETTSTOWN, NJ | $7,000 |
| HACKETTSTOWN PUBLIC SCHOOLS | HACKETTSTOWN, NJ | $7,000 |
Free toolbox talk
A 5-minute crew talk on 1910.304(b)(4), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1910.304(b)(4).
Related parts of this rule
- 1910.304(b) Branch circuits 279 citations
- 1910.304(b)(3) Ground-fault circuit interrupter protection for personnel 102 citations
- 1910.304(b)(4)(ii)(B) 70 citations
- 1910.304(b)(4)(ii) 70 citations
- 1910.304(b)(3)(i) 69 citations
- 1910.304(b)(2) Receptacles and cord connectors 37 citations
- 1910.304(b)(3)(ii) 30 citations
- 1910.304(b)(2)(ii) 23 citations
- 1910.304(b)(3)(ii)(C) 19 citations
- 1910.304(b)(3)(ii)(A) 10 citations
Get your crew competent
Trainers on Black Belt Safety: Marc Harvey, Dana Reyes
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Frequently asked questions
What is the basic rule for outlet devices?
They must have an ampere rating not less than the load to be served.
What lampholders are required on circuits over 20 amps?
Heavy-duty lampholders, rated not less than 660 watts if admedium type and not less than 750 watts for other types.
What rating does a single receptacle on its own branch circuit need?
An ampere rating of not less than that of the branch circuit.
About this page
Sources
- 29 CFR 1910.304 (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.