1910.333(b)(2)(iii): Applying Electrical Locks and Tags
Employers must place a lock and a tag on each disconnecting means used to deenergize circuits and equipment being worked on, with the lock attached so it cannot be operated without undue force or tools. Tags must prohibit unauthorized operation and removal. A tag alone is allowed if a lock cannot be applied or equivalent safety is shown, plus one more safety measure. A lock alone is allowed only under listed conditions.
Key takeaways
- 1910.333(b)(2)(iii) 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 19 inspections, with $46,219 in current penalties.
- 1 death is linked to inspections that cited this rule.
- Most citations: FL (3), IA (2), NH (2).
- Related part: 1910.333(b) Working on or near exposed deenergized parts (225 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1910.333(b)(2)(iii) ("Application of locks and tags") is one requirement inside 1910.333 Selection and use of work practices, 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
(iii) Application of locks and tags. 20 citations
(A) A lock and a tag shall be placed on each disconnecting means used to deenergize circuits and equipment on which work is to be performed, except as provided in paragraphs (b)(2)(iii)(C) and (b)(2)(iii)(E) of this section. The lock shall be attached so as to prevent persons from operating the disconnecting means unless they resort to undue force or the use of tools. Open (b)(2)(iii)(a) 18 citations
(B) Each tag shall contain a statement prohibiting unauthorized operation of the disconnecting means and removal of the tag. Open (b)(2)(iii)(b) 1 citations
(C) If a lock cannot be applied, or if the employer can demonstrate that tagging procedures will provide a level of safety equivalent to that obtained by the use of a lock, a tag may be used without a lock. 1 citations
(D) A tag used without a lock, as permitted by paragraph (b)(2)(iii)(C) of this section, shall be supplemented by at least one additional safety measure that provides a level of safety equivalent to that obtained by the use of a lock. Examples of additional safety measures include the removal of an isolating circuit element, blocking of a controlling switch, or opening of an extra disconnecting device. Open (b)(2)(iii)(d)
(E) A lock may be placed without a tag only under the following conditions: Open (b)(2)(iii)(e)
(1) Only one circuit or piece of equipment is deenergized, and
(2) The lockout period does not extend beyond the work shift, and
(3) Employees exposed to the hazards associated with reenergizing the circuit or equipment are familiar with this procedure.
Source: eCFR, text current as of 2026-10-15. Read all of 1910.333.
Injuries linked to this rule
1 death is linked to inspections where OSHA cited 1910.333(b)(2)(iii).
At 1:00 p.m. on June 24, 2024, Employee #1, employed as a maintenance technician, was working on an outside air unit when he came into contact with anelectrical source. The employee was electrocuted, sustaining fatal injuries fromthe electrical contact. Emergency services responded to the scene,…
Where and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 1 |
| 2024 | 9 |
| 2025 | 7 |
| 2026 | 3 |
Top states: FL (3), IA (2), NH (2), NV (1), KY (1)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| SOUTHERN TECHNICAL INSTITUTE, LLC | TAMPA, FL | $11,823 |
| SPOTSYLVANIA COUNTY PUBLIC SCHOOLS | FREDERICKSBURG, VA | $9,994 |
| 66605 - CREATIVE LIQUID COATINGS INC | NICHOLASVILLE, KY | $7,000 |
| BRI-STEEL MANUFACTURING | ENID, OK | $6,852 |
| TAMARACK MILL, LLC | NEW MEADOWS, ID | $4,550 |
Free toolbox talk
A 5-minute crew talk on 1910.333(b)(2)(iii), plus alerts when this rule changes. Free.
OSHA interpretation letters
- Clarification Regarding the Requirements of OSHA's Selection and Use of Work Practices Standard for Electrical Work (2026-08-17)
- Whether an LED type device ca be used for the isolation and deenergization verification requirements of 1910.147 and 1910.333. (2012-12-12)
- Clarification about 29 CFR 1910.333 and 29 CFR 1910.147 as they relate to work inside an electrical panel and on related equipment. (2006-07-28)
Related parts of this rule
- 1910.333(b) Working on or near exposed deenergized parts 225 citations
- 1910.333(b)(2) Lockout and tagging 223 citations
- 1910.333(b)(2)(i) Procedures 61 citations
- 1910.333(b)(2)(iv) 31 citations
- 1910.333(b)(2)(ii) Deenergizing equipment 31 citations
- 1910.333(b)(2)(iv)(B) 24 citations
- 1910.333(b)(2)(iii)(A) 18 citations
- 1910.333(b)(2)(ii)(A) 18 citations
- 1910.333(b)(2)(ii)(B) 12 citations
- 1910.333(b)(2)(v) Reenergizing equipment 4 citations
- 1910.333(b)(1) Application 2 citations
- 1910.333(b)(2)(iv)(A) 2 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 goes on each disconnecting means?
A lock and a tag, except as allowed in the rule.
When can a tag be used without a lock?
If a lock cannot be applied, or the employer shows tagging gives equivalent safety, and it must be supplemented by at least one additional safety measure.
When can a lock be used without a tag?
Only when one circuit or piece of equipment is deenergized, the lockout does not extend beyond the shift, and exposed employees are familiar with this procedure.
About this page
Sources
- 29 CFR 1910.333 (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.