1926.451(e)(4): Scaffold Stairtowers
Employers must position scaffold stairtowers so the bottom step is not more than 24 inches (61 cm) above the supporting level. Each stairway needs stairrails with a toprail and midrail on each side, handrails that give a good handhold without snag or puncture hazards, landings at least 18 by 18 inches at each level, slip-resistant treads, a slope between 40 and 60 degrees, and guardrails on open landing sides.
Key takeaways
- 1926.451(e)(4) is part of OSHA's construction standards (29 CFR Part 1926, Subpart L).
- OSHA cited it 16 times in the last 3 years, in 16 inspections, with $72,957 in current penalties.
- Most citations: IL (3), KY (2), GU (2).
- Related part: 1926.451(e) Access (924 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1926.451(e)(4) is one requirement inside 1926.451 General requirements, an OSHA construction standard (Part 1926, Subpart L). It includes 14 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) Stairtowers (scaffold stairway/towers) shall be positioned such that their bottom step is not more than 24 inches (61 cm.) above the scaffold supporting level. 16 citations
(i) A stairrail consisting of a toprail and a midrail shall be provided on each side of each scaffold stairway. 9 citations
(ii) The toprail of each stairrail system shall also be capable of serving as a handrail, unless a separate handrail is provided.
(iii) Handrails, and toprails that serve as handrails, shall provide an adequate handhold for employees grasping them to avoid falling.
(iv) Stairrail systems and handrails shall be surfaced to prevent injury to employees from punctures or lacerations, and to prevent snagging of clothing.
(v) The ends of stairrail systems and handrails shall be constructed so that they do not constitute a projection hazard.
(vi) Handrails, and toprails that are used as handrails, shall be at least 3 inches (7.6 cm) from other objects.
(vii) Stairrails shall be not less than 28 inches (71 cm) nor more than 37 inches (94 cm) from the upper surface of the stairrail to the surface of the tread, in line with the face of the riser at the forward edge of the tread.
(viii) A landing platform at least 18 inches (45.7 cm) wide by at least 18 inches (45.7 cm) long shall be provided at each level. 1 citations
(ix) Each scaffold stairway shall be at least 18 inches (45.7 cm) wide between stairrails.
(x) Treads and landings shall have slip-resistant surfaces.
(xi) Stairways shall be installed between 40 degrees and 60 degrees from the horizontal.
(xii) Guardrails meeting the requirements of paragraph (g)(4) of this section shall be provided on the open sides and ends of each landing. 6 citations
(xiii) Riser height shall be uniform, within 1⁄4 inch, (0.6 cm) for each flight of stairs. Greater variations in riser height are allowed for the top and bottom steps of the entire system, not for each flight of stairs.
(xiv) Tread depth shall be uniform, within 1⁄4 inch, for each flight of stairs.
Source: eCFR, text current as of 2026-10-15. Read all of 1926.451.
Where and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 2 |
| 2024 | 9 |
| 2025 | 4 |
| 2026 | 1 |
Top states: IL (3), KY (2), GU (2), LA (1), MO (1)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| ADJUSTABLE FORMS, INC. | CHICAGO, IL | $13,828 |
| MCCAIN FOODS USA, INC. | EASTON, ME | $8,619 |
| NEW HORIZON STEEL, LLC | CHICAGO, IL | $7,300 |
| AMBAR, INC. | CHICAGO, IL | $7,000 |
| BEST BID, INC. | MADISON HEIGHTS, VA | $6,885 |
Free toolbox talk
A 5-minute crew talk on 1926.451(e)(4), plus alerts when this rule changes. Free.
OSHA interpretation letters
- Scaffold step unit towers when used for access to locations other than scaffold platforms. (1992-10-27)
Related parts of this rule
- 1926.451(e) Access 924 citations
- 1926.451(e)(1) 792 citations
- 1926.451(e)(9) 38 citations
- 1926.451(e)(8) 28 citations
- 1926.451(e)(5) 27 citations
- 1926.451(e)(5)(i) 24 citations
- 1926.451(e)(9)(iv) 23 citations
- 1926.451(e)(6) 11 citations
- 1926.451(e)(9)(i) 11 citations
- 1926.451(e)(2) 9 citations
- 1926.451(e)(6)(i) 7 citations
- 1926.451(e)(2)(iii) 4 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
How high can the bottom step of a stairtower be?
Not more than 24 inches (61 cm) above the scaffold supporting level.
What height must stairrails be?
Not less than 28 inches (71 cm) nor more than 37 inches (94 cm) from the top of the stairrail to the tread surface, in line with the riser face.
At what angle must scaffold stairways be installed?
Between 40 degrees and 60 degrees from the horizontal.
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.