1926.451(c): Supported scaffold criteria
Supported scaffolds taller than 4 times their base width must be restrained from tipping with guys, ties or braces placed as the rule specifies, and ties or outriggers must be used whenever an eccentric load like a cantilevered platform is applied. Poles, legs, frames and uprights must rest on base plates and mud sills or another adequate firm foundation, and footings must be level, sound and rigid.
Key takeaways
- 1926.451(c) is part of OSHA's construction standards (29 CFR Part 1926, Subpart L).
- OSHA cited it 1,296 times in the last 3 years, in 1,113 inspections, with $3,655,278 in current penalties.
- 10 deaths are linked to inspections that cited this rule.
- Most citations: TX (119), VA (93), FL (90).
- Related part: 1926.451(c)(2) (1,056 citations).
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In this article
What this rule covers
29 CFR 1926.451(c) ("Criteria for supported scaffolds") is one requirement inside 1926.451 General requirements, an OSHA construction standard (Part 1926, Subpart L). It includes 11 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) Criteria for supported scaffolds. 1,296 citations
(1) Supported scaffolds with a height to base width (including outrigger supports, if used) ratio of more than four to one (4:1) shall be restrained from tipping by guying, tying, bracing, or equivalent means, as follows: Open (c)(1) 121 citations
(i) Guys, ties, and braces shall be installed at locations where horizontal members support both inner and outer legs. Open (c)(1)(i) 14 citations
(ii) Guys, ties, and braces shall be installed according to the scaffold manufacturer's recommendations or at the closest horizontal member to the 4:1 height and be repeated vertically at locations of horizontal members every 20 feet (6.1 m) or less thereafter for scaffolds 3 feet (0.91 m) wide or less, and every 26 feet (7.9 m) or less thereafter for scaffolds greater than 3 feet (0.91 m) wide. The top guy, tie or brace of completed scaffolds shall be placed no further than the 4:1 height from the top. Such guys, ties and braces shall be installed at each end of the scaffold and at horizontal intervals not to exceed 30 feet (9.1 m) (measured from one end [not both] towards the other). Open (c)(1)(ii) 35 citations
(iii) Ties, guys, braces, or outriggers shall be used to prevent the tipping of supported scaffolds in all circumstances where an eccentric load, such as a cantilevered work platform, is applied or is transmitted to the scaffold. Open (c)(1)(iii) 15 citations
(2) Supported scaffold poles, legs, posts, frames, and uprights shall bear on base plates and mud sills or other adequate firm foundation. Open (c)(2) 1,056 citations
(i) Footings shall be level, sound, rigid, and capable of supporting the loaded scaffold without settling or displacement. Open (c)(2)(i) 110 citations
(ii) Unstable objects shall not be used to support scaffolds or platform units. Open (c)(2)(ii) 77 citations
(iii) Unstable objects shall not be used as working platforms. Open (c)(2)(iii) 13 citations
(iv) Front-end loaders and similar pieces of equipment shall not be used to support scaffold platforms unless they have been specifically designed by the manufacturer for such use. Open (c)(2)(iv) 187 citations
(v) Fork-lifts shall not be used to support scaffold platforms unless the entire platform is attached to the fork and the fork-lift is not moved horizontally while the platform is occupied. Open (c)(2)(v) 225 citations
(3) Supported scaffold poles, legs, posts, frames, and uprights shall be plumb and braced to prevent swaying and displacement. Open (c)(3) 119 citations
Source: eCFR, text current as of 2026-10-15. Read all of 1926.451.
Injuries linked to this rule
10 deaths are linked to inspections where OSHA cited 1926.451(c).
At 2:07 p.m. on October 22, 2024, Employee #1 was performing exterior stone masonry work from a scaffold. The employee fell from the scaffold and struck hishead on palletized stone pieces below. The fall resulted in fatal head trauma and a brain bleed.
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 | 95 |
| 2024 | 436 |
| 2025 | 464 |
| 2026 | 301 |
Top states: TX (119), VA (93), FL (90), MD (88), NJ (77)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| THOMAS BUILDERS OF VIRGINIA, INC. | DALEVILLE, VA | $162,965 |
| CREATIVE MASONRY, INC. | JONESBOROUGH, TN | $108,000 |
| ROAD CONTRACTOR CORPORATION | WILLIAMSTOWN, NJ | $78,080 |
| MILLER CARPENTRY, LLC | MAHOMET, IL | $34,048 |
| ACE II LLC | BELMAR, NJ | $32,265 |
Free toolbox talk
A 5-minute crew talk on 1926.451(c), plus alerts when this rule changes. Free.
OSHA interpretation letters
- Whether an employer is permitted to double wrap #9 gage steel wire in order to guy, tie or brace a scaffold. (2010-03-26)
- Whether it is permissible to use a concrete block hanging on a coupling pin as a counterweight to prevent a scaffold from tipping. (2005-06-17)
- Whether a safety factor must be incorporated into the design of footings for supported scaffolds. (2005-04-11)
- Tie-in requirements for supported scaffolds; errors in Non-Mandatory Appendix E. (2005-04-08)
- Height to base width ratio for mobile scaffolds with/without outriggers. (2004-03-10)
- Clarification of requirements for construction scaffold erection/dismantling; safe means of access; blocks for two-point suspension scaffolds. (2002-01-02)
- Applicable standards to lifting personnel on a platform supported by a rough-terrain forklift. (2001-11-27)
- Access requirements for cantilevered work platforms; use of unstable objects is prohibited. (2001-07-23)
- Tie, guy, and bracing requirements for scaffold systems. (2000-08-04)
- Foundation requirements for scaffolds; competent person qualifications for assessing foundations. (2000-08-01)
- Forklifts in construction: elevating personnel and operator training. (1999-09-30)
- Use of flexible cords for connection of appliances; scaffold base plates. (1998-07-20)
- Tying or guying of supported scaffolds. (1998-04-02)
- Scaffolds: removal of bracing; maximum loads; damaged planking; and foundations. (1997-11-25)
- New Fall Protection standards and standards for scaffolds used during dry wall work (1995-03-13)
Related parts of this rule
- 1926.451(c)(2) 1,056 citations
- 1926.451(c)(2)(v) 225 citations
- 1926.451(c)(2)(iv) 187 citations
- 1926.451(c)(1) 121 citations
- 1926.451(c)(3) 119 citations
- 1926.451(c)(2)(i) 110 citations
- 1926.451(c)(2)(ii) 77 citations
- 1926.451(c)(1)(ii) 35 citations
- 1926.451(c)(1)(iii) 15 citations
- 1926.451(c)(1)(i) 14 citations
- 1926.451(c)(2)(iii) 13 citations
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Frequently asked questions
When does a supported scaffold need to be tied off?
When its height to base width ratio, including outriggers, is more than 4 to 1.
Can scaffold legs sit directly on dirt?
They must bear on base plates and mud sills or other adequate firm foundation.
About this page
Sources
- 29 CFR 1926.451 (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 2026-10-19
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.