OSHA construction scaffolds study guide
Subpart L of the OSHA construction standards (29 CFR 1926.450 to 1926.454) sets the federal rules for scaffolds used in construction. This guide sets out what the rule text states on capacity, platform construction, access, safe use, fall protection, falling object protection, the duties of competent and qualified persons, and training. Every point links to the section it comes from, with the exact words quoted. It is a study aid, not training, and the appendices to Subpart L are non-mandatory.
Scope and key definitions
Subpart L applies to all scaffolds used in workplaces covered by Part 1926. It does not apply to crane or derrick suspended personnel platforms, and aerial lifts are covered only by 1926.453.
“This subpart applies to all scaffolds used in workplaces covered by this part. It does not apply to crane or derrick suspended personnel platforms. The criteria for aerial lifts are set out exclusively in § 1926.453.”
29 CFR 1926.450, Scope, application and definitions applicable to this subpart
A competent person can identify existing and predictable hazards and has the authority to take prompt corrective measures to eliminate them. Both parts are needed.
“Competent person means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.”
29 CFR 1926.450, Scope, application and definitions applicable to this subpart
A qualified person has a recognized degree, certificate or professional standing, or has shown by extensive knowledge, training and experience that they can solve problems related to the subject matter, the work or the project.
“Qualified means one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated his/her ability to solve or resolve problems related to the subject matter, the work, or the project.”
29 CFR 1926.450, Scope, application and definitions applicable to this subpart
Maximum intended load is the total of all persons, equipment, tools, materials, transmitted loads and other loads reasonably expected on the scaffold or component at any one time.
“Maximum intended load means the total load of all persons, equipment, tools, materials, transmitted loads, and other loads reasonably anticipated to be applied to a scaffold or scaffold component at any one time.”
29 CFR 1926.450, Scope, application and definitions applicable to this subpart
Not covered here
We do not cover aerial lifts (1926.453), which set their own rules and refer to ANSI A92.2-1969 for design and construction, or the extra rules for each specific scaffold type in 1926.452. We only write what an official source states, so study these parts with your certifying program's materials.
Capacity
Except as provided in paragraphs (a)(2) through (a)(5) and (g) of 1926.451, each scaffold and scaffold component must support, without failure, its own weight and at least 4 times the maximum intended load applied or transmitted to it.
“Except as provided in paragraphs (a)(2), (a)(3), (a)(4), (a)(5) and (g) of this section, each scaffold and scaffold component shall be capable of supporting, without failure, its own weight and at least 4 times the maximum intended load applied or transmitted to it.”
Each suspension rope, including connecting hardware, on a non-adjustable suspension scaffold must support at least 6 times the maximum intended load applied or transmitted to that rope.
“Each suspension rope, including connecting hardware, used on non-adjustable suspension scaffolds shall be capable of supporting, without failure, at least 6 times the maximum intended load applied or transmitted to that rope.”
Scaffolds must be designed by a qualified person and built and loaded according to that design. Appendix A, which is non-mandatory, gives example criteria.
“Scaffolds shall be designed by a qualified person and shall be constructed and loaded in accordance with that design. Non-mandatory appendix A to this subpart contains examples of criteria that will enable an employer to comply with paragraph (a) of this section.”
Scaffolds and components may not be loaded beyond their maximum intended loads or rated capacities, whichever is less.
“Scaffolds and scaffold components shall not be loaded in excess of their maximum intended loads or rated capacities, whichever is less.”
Platform construction
Each platform on all working levels of scaffolds must be fully planked or decked between the front uprights and the guardrail supports.
“Each platform on all working levels of scaffolds shall be fully planked or decked between the front uprights and the guardrail supports”
Each platform unit must be installed so the space between adjacent units, and between the platform and the uprights, is no more than 1 inch 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).
“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).”
Full planking is not required on platforms used only as walkways or only by employees erecting or dismantling the scaffold. There, only the planking the employer establishes is necessary for safe working conditions is required.
“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.”
Except as provided in (b)(2)(i) and (ii), each scaffold platform and walkway must be at least 18 inches wide.
“Except as provided in paragraphs (b)(2)(i) and (b)(2)(ii) of this section, each scaffold platform and walkway shall be at least 18 inches (46 cm) wide.”
Except as provided in (b)(3)(i) and (ii), the front edge of all platforms may be no more than 14 inches from the face of the work, unless guardrail systems are erected along the front edge and/or personal fall arrest systems are used in accordance with paragraph (g) to protect employees from falling.
“Except as provided in paragraphs (b)(3) (i) and (ii) of this section, the front edge of all platforms shall not be more than 14 inches (36 cm) from the face of the work, unless guardrail systems are erected along the front edge and/or personal fall arrest systems are used in accordance with paragraph (g) of this section to protect employees from falling.”
Those exceptions: the maximum distance from the face is 3 inches for outrigger scaffolds and 18 inches for plastering and lathing operations.
“The maximum distance from the face for outrigger scaffolds shall be 3 inches (8 cm); (ii) The maximum distance from the face for plastering and lathing operations shall be 18 inches (46 cm).”
Unless cleated or otherwise restrained by hooks or equivalent means, each end of a platform must extend over the centerline of its support by at least 6 inches.
“Each end of a platform, unless cleated or otherwise restrained by hooks or equivalent means, shall extend over the centerline of its support at least 6 inches (15 cm).”
Each end of a platform 10 feet or less long may not extend over its support more than 12 inches, unless the platform is designed and installed so that the cantilevered portion can support employees and/or materials without tipping, or has guardrails that block employee access to the cantilevered end.
“Each end of a platform 10 feet or less in length shall not extend over its support more than 12 inches (30 cm) unless the platform is designed and installed so that the cantilevered portion of the platform is able to support employees and/or materials without tipping, or has guardrails which block employee access to the cantilevered end.”
Each platform longer than 10 feet may not extend over its support more than 18 inches, unless it is designed and installed so that the cantilevered portion can support employees without tipping, or has guardrails that block employee access to the cantilevered end.
“Each platform greater than 10 feet in length shall not extend over its support more than 18 inches (46 cm), unless it is designed and installed so that the cantilevered portion of the platform is able to support employees without tipping, or has guardrails which block employee access to the cantilevered end.”
Supported scaffolds: footing and tipping
A supported scaffold with a height to base width ratio of more than 4:1 (including outrigger supports, if used) must be restrained from tipping by guying, tying, bracing or equivalent means.
“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”
Poles, legs, posts, frames and uprights of supported scaffolds must bear on base plates and mud sills or another adequate firm foundation.
“Supported scaffold poles, legs, posts, frames, and uprights shall bear on base plates and mud sills or other adequate firm foundation.”
Unstable objects may not be used to support scaffolds or platform units, or as working platforms.
“Unstable objects shall not be used to support scaffolds or platform units. (iii) Unstable objects shall not be used as working platforms.”
Access
When a scaffold platform is more than 2 feet above or below a point of access, a listed means of access (ladders, stair towers, ramps, walkways, integral access, direct access and similar) must be used. Crossbraces may not be used as a means of access.
“When scaffold platforms are more than 2 feet (0.6 m) above or below a point of access, portable ladders, hook-on ladders, attachable ladders, stair towers (scaffold stairways/towers), stairway-type ladders (such as ladder stands), ramps, walkways, integral prefabricated scaffold access, or direct access from another scaffold, structure, personnel hoist, or similar surface shall be used. Crossbraces shall not be used as a means of access.”
Hook-on and attachable ladders must have their bottom rung no more than 24 inches above the scaffold supporting level.
“Hook-on and attachable ladders shall be positioned so that their bottom rung is not more than 24 inches (61 cm) above the scaffold supporting level”
Ramps and walkways 6 feet or more above lower levels must have guardrail systems that comply with Subpart M (Fall Protection).
“Ramps and walkways 6 feet (1.8 m) or more above lower levels shall have guardrail systems which comply with subpart M of this part—Fall Protection”
No ramp or walkway may be inclined more than a slope of 1 vertical to 3 horizontal (20 degrees above the horizontal).
“No ramp or walkway shall be inclined more than a slope of one (1) vertical to three (3) horizontal (20 degrees above the horizontal).”
Direct access to or from another surface is allowed only when the scaffold is no more than 14 inches horizontally and no more than 24 inches vertically from that surface.
“Direct access to or from another surface shall be used only when the scaffold is not more than 14 inches (36 cm) horizontally and not more than 24 inches (61 cm) vertically from the other surface.”
For employees erecting or dismantling supported scaffolds (effective September 2, 1997), the employer must provide safe means of access where it is feasible and does not create a greater hazard. A competent person decides whether it is feasible or would pose a greater hazard, based on site conditions and the type of scaffold being erected or dismantled.
“Effective September 2, 1997, access for employees erecting or dismantling supported scaffolds shall be in accordance with the following: (i) The employer shall provide safe means of access for each employee erecting or dismantling a scaffold where the provision of safe access is feasible and does not create a greater hazard. The employer shall have a competent person determine whether it is feasible or would pose a greater hazard to provide, and have employees use a safe means of access. This determination shall be based on site conditions and the type of scaffold being erected or dismantled.”
Use of scaffolds
A competent person must inspect scaffolds and components for visible defects before each work shift and after any occurrence that could affect structural integrity.
“Scaffolds and scaffold components shall be inspected for visible defects by a competent person before each work shift, and after any occurrence which could affect a scaffold's structural integrity.”
Any part of a scaffold damaged or weakened so that its strength is less than paragraph (a) requires must be immediately repaired or replaced, braced to meet those provisions, or removed from service until repaired.
“Any part of a scaffold damaged or weakened such that its strength is less than that required by paragraph (a) of this section shall be immediately repaired or replaced, braced to meet those provisions, or removed from service until repaired.”
Scaffolds may not be moved horizontally with employees on them unless designed by a registered professional engineer for that movement or, for mobile scaffolds, the rules in 1926.452(w) are followed.
“Scaffolds shall not be moved horizontally while employees are on them, unless they have been designed by a registered professional engineer specifically for such movement or, for mobile scaffolds, where the provisions of § 1926.452(w) are followed.”
Scaffolds may be erected, moved, dismantled or altered only under the supervision and direction of a competent person qualified in that work, and only by experienced and trained employees the competent person selects.
“Scaffolds shall be erected, moved, dismantled, or altered only under the supervision and direction of a competent person qualified in scaffold erection, moving, dismantling or alteration. Such activities shall be performed only by experienced and trained employees selected for such work by the competent person.”
Employees may not work on scaffolds covered with snow, ice or other slippery material, except as needed to remove it.
“Employees shall be prohibited from working on scaffolds covered with snow, ice, or other slippery material except as necessary for removal of such materials.”
Work during storms or high winds is prohibited unless a competent person has determined it is safe and the employees are protected by a personal fall arrest system or wind screens.
“Work on or from scaffolds is prohibited during storms or high winds unless a competent person has determined that it is safe for employees to be on the scaffold and those employees are protected by a personal fall arrest system or wind screens.”
Clearance from power lines
Scaffolds may not be erected, used, dismantled, altered or moved such that they, or any conductive material handled on them, might come closer to exposed and energized power lines than the distances in the rule's table.
“Scaffolds shall not be erected, used, dismantled, altered, or moved such that they or any conductive material handled on them might come closer to exposed and energized power lines than as follows:”
Insulated lines (table rows, minimum distance column): less than 300 volts, 3 feet; 300 volts to 50 kV, 10 feet; more than 50 kV, 10 feet plus 0.4 inches for each 1 kV over 50 kV. The more-than-50 kV row also has an entry in the Alternatives column (see below).
“Insulated lines voltage Less than 300 volts Minimum distance Alternatives 3 feet (0.9 m) Insulated lines voltage Minimum distance 300 volts to 50 kv 10 feet (3.1m) More than 50 kv 10 feet (3.1 m) plus 0.4 inches (1.0 cm) for each 1 kv over 50 kv”
Uninsulated lines (table rows, minimum distance column): less than 50 kV, 10 feet; more than 50 kV, 10 feet plus 0.4 inches for each 1 kV over 50 kV. The more-than-50 kV row also has an entry in the Alternatives column (see below).
“Uninsulated lines voltage Minimum distance Less than 50 kv 10 feet (3.1 m) More than 50 kv 10 feet (3.1 m) plus 0.4 inches (1.0 cm) for each 1 kv over 50 kv”
For the more-than-50 kV rows (insulated and uninsulated), the table's Alternatives column lists 2 times the length of the line insulator, but never less than 10 feet.
“2 times the length of the line insulator, but never less than 10 feet (3.1 m).”
Scaffolds and materials may be closer than the table allows only where that clearance is necessary for the work, and only after the utility company or electrical system operator has been notified and has deenergized the lines, relocated them, or installed protective coverings to prevent accidental contact.
“Scaffolds and materials may be closer to power lines than specified above where such clearance is necessary for performance of work, and only after the utility company, or electrical system operator, has been notified of the need to work closer and the utility company, or electrical system operator, has deenergized the lines, relocated the lines, or installed protective coverings to prevent accidental contact with the lines.”
Fall protection on scaffolds
Each employee on a scaffold more than 10 feet above a lower level must be protected from falling to that lower level. Paragraphs (g)(1)(i) through (vii) set the type of fall protection for each type of scaffold.
“Each employee on a scaffold more than 10 feet (3.1 m) above a lower level shall be protected from falling to that lower level. Paragraphs (g)(1) (i) through (vii) of this section establish the types of fall protection to be provided to the employees on each type of scaffold.”
On a boatswains' chair, catenary, float, needle beam or ladder jack scaffold, each employee must be protected by a personal fall arrest system.
“Each employee on a boatswains' chair, catenary scaffold, float scaffold, needle beam scaffold, or ladder jack scaffold shall be protected by a personal fall arrest system”
On a single-point or two-point adjustable suspension scaffold, each employee needs both a personal fall arrest system and a guardrail system.
“Each employee on a single-point or two-point adjustable suspension scaffold shall be protected by both a personal fall arrest system and guardrail system”
On scaffolds not otherwise listed, each employee must be protected by personal fall arrest systems or guardrail systems that meet (g)(4).
“For all scaffolds not otherwise specified in paragraphs (g)(1)(i) through (g)(1)(vi) of this section, each employee shall be protected by the use of personal fall arrest systems or guardrail systems meeting the requirements of paragraph (g)(4) of this section.”
For employees erecting or dismantling supported scaffolds, a competent person must determine the feasibility and safety of fall protection, and the employer must provide it where it is feasible and does not create a greater hazard.
“the employer shall have a competent person determine the feasibility and safety of providing fall protection for employees erecting or dismantling supported scaffolds. Employers are required to provide fall protection for employees erecting or dismantling supported scaffolds where the installation and use of such protection is feasible and does not create a greater hazard.”
When vertical lifelines are used, they must be fastened to a fixed safe point of anchorage, be independent of the scaffold, and be protected from sharp edges and abrasion. Safe anchorages include structural members of buildings, but not standpipes, vents, other piping, electrical conduit, outrigger beams or counterweights.
“When vertical lifelines are used, they shall be fastened to a fixed safe point of anchorage, shall be independent of the scaffold, and shall be protected from sharp edges and abrasion. Safe points of anchorage include structural members of buildings, but do not include standpipes, vents, other piping systems, electrical conduit, outrigger beams, or counterweights.”
Guardrail systems installed to meet the requirements of § 1926.451 must be installed along all open sides and ends of platforms, and before the scaffold is released for use by employees other than erection/dismantling crews.
“Guardrail systems shall be installed along all open sides and ends of platforms. Guardrail systems shall be installed before the scaffold is released for use by employees other than erection/dismantling crews.”
On supported scaffolds manufactured or placed in service after January 1, 2000, the top edge of the toprail must be between 38 and 45 inches above the platform. Older supported scaffolds, and suspended scaffolds that need both a guardrail and a personal fall arrest system, use 36 to 45 inches.
“The top edge height of toprails or equivalent member on supported scaffolds manufactured or placed in service after January 1, 2000 shall be installed between 38 inches (0.97 m) and 45 inches (1.2 m) above the platform surface. The top edge height on supported scaffolds manufactured and placed in service before January 1, 2000, and on all suspended scaffolds where both a guardrail and a personal fall arrest system are required shall be between 36 inches (0.9 m) and 45 inches (1.2 m).”
Each toprail or equivalent member must withstand, without failure, a force in any downward or horizontal direction at any point along its top edge of at least 100 pounds on single-point or two-point adjustable suspension scaffolds, and at least 200 pounds on all other scaffolds.
“Each toprail or equivalent member of a guardrail system shall be capable of withstanding, without failure, a force applied in any downward or horizontal direction at any point along its top edge of at least 100 pounds (445 n) for guardrail systems installed on single-point adjustable suspension scaffolds or two-point adjustable suspension scaffolds, and at least 200 pounds (890 n) for guardrail systems installed on all other scaffolds.”
Midrails, screens, mesh, intermediate vertical members, solid panels and equivalent members must withstand, without failure, at least 75 pounds on guardrail systems with a minimum 100 pound toprail capacity, and at least 150 pounds on those with a minimum 200 pound toprail capacity.
“Midrails, screens, mesh, intermediate vertical members, solid panels, and equivalent structural members of a guardrail system shall be capable of withstanding, without failure, a force applied in any downward or horizontal direction at any point along the midrail or other member of at least 75 pounds (333 n) for guardrail systems with a minimum 100 pound toprail capacity, and at least 150 pounds (666 n) for guardrail systems with a minimum 200 pound toprail capacity.”
Falling object protection
In addition to wearing hardhats, each employee on a scaffold must be given additional protection from falling hand tools, debris and other small objects: toeboards, screens or guardrail systems, or debris nets, catch platforms or canopy structures that contain or deflect the falling objects.
“In addition to wearing hardhats each employee on a scaffold shall be provided with additional protection from falling hand tools, debris, and other small objects through the installation of toeboards, screens, or guardrail systems, or through the erection of debris nets, catch platforms, or canopy structures that contain or deflect the falling objects.”
Where tools, materials or equipment could fall from a scaffold and strike employees below, one of the listed options is to barricade the area below to which objects can fall and not permit employees to enter it.
“Where there is a danger of tools, materials, or equipment falling from a scaffold and striking employees below, the following provisions apply: (i) The area below the scaffold to which objects can fall shall be barricaded, and employees shall not be permitted to enter the hazard area”
Another option is a toeboard along the edge of platforms more than 10 feet above lower levels, for a distance sufficient to protect employees below; on float (ship) scaffolds an edging of 3/4 × 1 1/2 inch wood or equivalent may be used instead.
“A toeboard shall be erected along the edge of platforms more than 10 feet (3.1 m) above lower levels for a distance sufficient to protect employees below, except on float (ship) scaffolds where an edging of 3⁄4 × 11⁄2 inch (2 × 4 cm) wood or equivalent may be used in lieu of toeboards”
Where used, toeboards must withstand, without failure, a force of at least 50 pounds applied in any downward or horizontal direction at any point along the toeboard.
“Capable of withstanding, without failure, a force of at least 50 pounds (222 n) applied in any downward or horizontal direction at any point along the toeboard”
Where used, toeboards must be at least 3.5 inches high from their top edge to the walking/working surface, securely fastened at the outermost edge of the platform, with no more than 1/4 inch clearance above the surface, and solid or with openings no more than 1 inch in the greatest dimension.
“At least three and one-half inches (9 cm) high from the top edge of the toeboard to the level of the walking/working surface. Toeboards shall be securely fastened in place at the outermost edge of the platform and have not more than 1⁄4 inch (0.7 cm) clearance above the walking/ working surface. Toeboards shall be solid or with openings not over one inch (2.5 cm) in the greatest dimension.”
Training
Each employee who works while on a scaffold must be trained by a person qualified in the subject matter to recognize the hazards of the type of scaffold used and understand the procedures to control or minimize them.
“The employer shall have each employee who performs work while on a scaffold trained by a person qualified in the subject matter to recognize the hazards associated with the type of scaffold being used and to understand the procedures to control or minimize those hazards.”
Each employee involved in erecting, disassembling, moving, operating, repairing, maintaining or inspecting a scaffold must be trained by a competent person to recognize any hazards associated with that work.
“The employer shall have each employee who is involved in erecting, disassembling, moving, operating, repairing, maintaining, or inspecting a scaffold trained by a competent person to recognize any hazards associated with the work in question.”
When the employer has reason to believe an employee lacks the skill or understanding needed for safe scaffold work, the employer must retrain the employee. Retraining is required at least where changes at the worksite present a hazard the employee has not been trained on.
“When the employer has reason to believe that an employee lacks the skill or understanding needed for safe work involving the erection, use or dismantling of scaffolds, the employer shall retrain each such employee so that the requisite proficiency is regained. Retraining is required in at least the following situations: (1) Where changes at the worksite present a hazard about which an employee has not been previously trained; or”
Retraining is also required where changes in the types of scaffolds, fall protection, falling object protection or other equipment present a hazard the employee has not been trained on, and where inadequacies in the employee's scaffold work show they have not retained the requisite proficiency.
“Where changes in the types of scaffolds, fall protection, falling object protection, or other equipment present a hazard about which an employee has not been previously trained; or (3) Where inadequacies in an affected employee's work involving scaffolds indicate that the employee has not retained the requisite proficiency.”
Sources
- eCFR: 29 CFR 1926.450, Scope, application and definitions applicable to this subpart (as of Nov 3, 2026)Checked November 5, 2026
- eCFR: 29 CFR 1926.451, General requirements (as of Nov 3, 2026)Checked November 5, 2026
- eCFR: 29 CFR 1926.454, Training requirements (as of Nov 3, 2026)Checked November 5, 2026
Other OSHA Construction study guides: Introduction to OSHA, Fall protection, Stairways and ladders, Electrical safety, Excavations, Personal protective equipment, Health hazards, Hazard communication, Respirable crystalline silica, Welding and cutting, General safety and health