# height-to-base-ratio-tying-trigger — Every numeric dimensional tolerance and safety factor in OSHA's scaffold general requirements (29 CFR 1926.451)

For height-to-base-ratio-tying-trigger, paragraph citation is 1926.451(c)(1); type of requirement is height-to-base ratio trigger; value (imperial) is four to one (4:1); applies to is Supported scaffolds with a height to base width (including outrigger supports, if used) ratio of more than four to one (4:1); regulation section heading is Criteria for supported scaffolds, recorded from its source on 2026-08-31; source re-checked 2026-09-14.

- **Requirement ID:** height-to-base-ratio-tying-trigger _(our reading, not quoted from the source)_
- **Paragraph citation:** 1926.451(c)(1) _(our reading, not quoted from the source)_
- **Type of requirement:** height-to-base ratio trigger _(our reading, not quoted from the source)_
- **Value (imperial):** four to one (4:1) _(verified: appears in the quote below)_
- **Applies to:** Supported scaffolds with a height to base width (including outrigger supports, if used) ratio of more than four to one (4:1) _(verified: appears in the quote below)_
- **Regulation section heading:** Criteria for supported scaffolds _(verified: appears in its own passage below)_

## What the source says

> (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:

## Where each value comes from

This source states these in separate places, so each value is shown with the passage that states it.

### Regulation section heading

> (c) Criteria for supported scaffolds.

## Source

- https://www.ecfr.gov/current/title-29/subtitle-B/chapter-XVII/part-1926/subpart-L/section-1926.451

Last verified: 2026-09-14. Review by: 2027-08-31.
Part of [Every numeric dimensional tolerance and safety factor in OSHA's scaffold general requirements (29 CFR 1926.451)](https://referencesource.org/osha-scaffold-dimensional-tolerances/).