OSHA 1926.451(b)(1): fully planked scaffold platforms
Under 29 CFR 1926.451(b)(1), every scaffold platform on every working level must be fully planked or decked between the front uprights and the guardrail supports, with no more than 1 inch between adjacent platform units unless the employer can show a wider space is necessary.
Official text
(1) Each platform on all working levels of scaffolds shall be fully planked or decked between the front uprights and the guardrail supports as follows: (i) Each platform unit (e.g., scaffold plank, fabricated plank, fabricated deck, or fabricated platform) shall be installed so that the space between adjacent units and the space between the platform and the uprights is no more than 1 inch (2.5 cm) wide, except where the employer can demonstrate that a wider space is necessary (for example, to fit around uprights when side brackets are used to extend the width of the platform). (ii) Where the employer makes the demonstration provided for in paragraph (b)(1)(i) of this section, the platform shall be planked or decked as fully as possible and the remaining open space between the platform and the uprights shall not exceed 9 1/2 inches (24.1 cm). Exception to paragraph (b)(1): The requirement in paragraph (b)(1) to provide full planking or decking does not apply to platforms used solely as walkways or solely by employees performing scaffold erection or dismantling. In these situations, only the planking that the employer establishes is necessary to provide safe working conditions is required.Read the full section on eCFR
What it requires, in plain English
- Platform units are installed so gaps between units, and between the platform and the uprights, are no more than 1 inch wide, except where a wider space is shown to be necessary.
- Where full planking is not possible, the platform is planked as fully as possible and the open space between the platform and the guardrail supports does not exceed 9½ inches.
- Scaffolds are inspected by a competent person before each work shift under 1926.451(f)(3).
Where it shows up on site
- A plank pulled to pass material up and never replaced
- Mixed plank widths leaving a gap at the inside face
- Decks short of the uprights at a corner or return
Verify on site before you call it
A photo rarely shows every fact a standard depends on. Confirm these in person before treating the condition as a violation:
- What is the platform height above the lower level?
- Is the gap an intentional access opening or an unsecured deck gap?
- Is the platform a working level or used solely as a walkway or for erection/dismantling?
- What is the measured width of the gap between adjacent platform units?
Typical corrective actions
- Have a competent person inspect the platform and determine whether the gap is an intentional access opening or an unsecured deck gap.
- If unsecured, close the gap by installing additional planking/decking or securing the platform units so spacing is within allowed limits.
- If the gap is an intentional access opening, ensure it is protected by guardrails or a personal fall arrest system as required.
Related standards
This guide summarizes federal OSHA construction standards for general information. It is not legal advice. States with their own OSHA-approved plans may set different or additional requirements; see federal and state coverage.