Scaffolding Home Frequently Asked Questions
- General Information
- Summary and Explanation of the Final Rule
- General Requirements For Scaffolds
- Specific Scaffold Requirements
- Aerial Lift Requirements
On August 30, 1996, OSHA issued revised standards for scaffolds. The revised standard, known as "Safety Standards for Scaffolds Used in the Construction Industry," is found in Title 29 Code of Federal Regulations (CFR) Part 1926, Subpart L. The final rule updates the existing construction scaffold standards in Subpart L. The new standards set performance-based criteria to protect employees from scaffold-related hazards such as falls, failing objects, structural instability, electrocution, or overloading.
The new final rule addresses training and various types of scaffolds, as well as falling object protection, ladders, weather conditions, aerial lifts, stilts, and other matters that were not previously covered by the OSHA scaffold standards. In addition, it allows employers more flexibility when using protective systems for workers on scaffolding. The language of the rule has been simplified by eliminating duplicative and outdated provisions, consolidating overlapping requirements, and enhancing performance-based criteria to allow employers more flexibility in compliance while still protecting employees.
Subpart L of 29 CFR 1926 applies to scaffolds and aerial lifts in the construction industry. This standard includes provisions on scaffold capacity, scaffold platform construction, use of scaffolds, fall protection, and falling object protection. The standard also includes requirements applicable to specific types of scaffolds and addresses erecting and dismantling scaffolds.
November 29, 1996-90 days from the date of publication of the final rule in the Federal Register (FR 61:46025-46075, Friday, August 30, 1996). Information collection requirements (i.e., written certification) become effective when the Office of Management and Budget takes action in accordance with the Paperwork Reduction Act of 1995. Written comments on the paperwork requirements for the final rule had to be submitted on or before October 30, 1996 - 60 days after initial publication of the rule in the Federal Register.
The agency issued new standards to simplify and update the previous standards in use since May 1971. (see Federal Register) OSHA developed the new standards with the input of many industry representatives to better protect the estimated 2.3 million construction workers (about 65 percent of the construction industry workforce) working on scaffolds regularly. The agency estimates the new standards will prevent about 4,455 injuries and 47 deaths each year, saving employers $90 million annually in lost-workday costs resulting from scaffold-related injuries.
All employers and their employees using scaffolds in the construction industry must be familiar with these standards. A copy of the regulatory text appears at the end of this publication. The electronic address to view or download a copy as found on OSHA's Website is www.osha.gov. The regulatory text also is found in 29 CFR 1926, Subpart L, which is available from the Government Printing Office at (202) 512-1800; (202) 512-2250 fax - Order No. S/N 869-034-00107-6; cost $30 (foreign $37.50).
29 CFR contains other standards that apply to construction work such as the responsibility to initiate and maintain programs [29 CFR 1926.20(b)(1)]; exposures to dusts and chemicals [29 CFR 1926.33, 29 CFR 1926.55, 29 CFR 1926.59, 29 CFR 1926.62, and 29 CFR 1926.1101]; hand and power tools [29 CFR 1926.300-1926.307]; electrical [29 CFR 1926.400-1926.449]; personal fall arrest systems [29 CFR 1926.502]; and ladders [29 CFR 1926.1050-1926.1060].
Summary and Explanation of the Final Rule
Employers and employees should be familiar with seven key provisions of the revised scaffolding standard:
- The standard requires fall protection at a 10 foot height above a lower level for employees. [29 CFR 1926.451(g)(1)]
- Guardrail height - The height of the toprail for scaffolds manufactured and placed in service before January 1, 2000 can be between 36 inches (0.9 m) and 45 inches (1.2 m). The height of the toprail for scaffolds manufactured and placed in service after January 1, 2000 must be between 38 inches (0.97 m) and 45 inches (1.2 m). [29 CFR 1926.451(g)(4)(ii)] When the crosspoint of crossbracing is used as a toprail, it must be between 38 inches (0.97 m) and 48 inches (1.3 m) above the work platform. [29 CFR 1926.451(g)(4)(xv)] Midrails must be installed approximately halfway between the toprail and the platform surface. [29 CFR 1926.451(g)(4)(iv)] When a crosspoint of crossbracing is used as a midrail, it must be between 20 inches (0.5 m) and 30 inches (0.8 m) above the work platform. [29 CFR 1926.451(g)(4)(xv)]
- Erecting and Dismantling - When erecting and dismantling supported scaffolds, a competent person must determine the feasibility of providing a safe means of access and fall protection for these operations. [29 CFR 1926.451(e)(9) and 29 CFR 1926.451(g)(2)]
- Training - Employers must train each employee who works on a scaffold on the procedures to control or minimize the hazards. [29 CFR 1926.454]
- Inspections - Before each work shift and after any occurrence that could affect the structural integrity, a competent person must inspect the scaffold and scaffold components for visible defects. [29 CFR 1926.451(f)(3)]
- Overhand bricklaying - A guardrail or personal fall arrest system on all sides except the side where the work is being done must protect employees doing overhand bricklaying from supported scaffolds. [29 CFR 1926.451(g)(1)(vi)] The standards for aerial lifts have been relocated from 29 CFR 1926.556 to 29 CFR 1926.453.
OSHA's scaffolding standard defines a competent person as "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(b)]
The standard requires a competent person to perform the following duties under these circumstances:
- In General:
- To select and direct employees who erect, dismantle, move, or alter scaffolds. [29 CFR 1926.451(f)(7)]
- To determine if it is safe for employees to work on or from a scaffold during storms or high winds and to ensure that a personal fall arrest system or wind screens protect these employees. (Note: Wind screens should not be used unless the scaffold is secured against the anticipated wind forces imposed.) [29 CFR 1926.451(f)(12)]
- For Training:
- To train employees involved in erecting, disassembling, moving, operating, repairing, maintaining, or inspecting scaffolds to recognize associated work hazards. [29 CFR 1926.454(b)]
- For Inspections:
- To inspect scaffolds and scaffold components for visible defects before each work shift and after any occurrence which could affect the corrective actions. [29 CFR 1926.451(f)(3)]
- To inspect ropes on suspended scaffolds prior to each workshift and after every occurrence which could affect the structural integrity and to authorize prompt corrective actions. [29 CFR 1926.451(d)(10)]
- To inspect manila or plastic (or other synthetic) rope being used for toprails or midrails. [29 CFR 1926.451(g)(4)(xiv)]
- For Suspension Scaffolds:
- For Erectors and Dismantlers:
- For Scaffold Components:
The standard defines a qualified person as "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(b)]
The qualified person must perform the following duties in these circumstances:
- In General:
- To design and load scaffolds in accordance with that design. [29 CFR 1926.451(a)(6)]
- For Training:
- To train employees working on the scaffolds to recognize the associated hazards and understand procedures to control or minimize those hazards. [29 CFR 1926.454(a)]
- For Suspension Scaffolds:
- To design the rigging for single-point adjustable suspension scaffolds. [29 CFR 1926.452(o)(2)(i)]
- To design platforms on two-point adjustable suspension types that are less than 36 inches (0.9 in) wide to prevent instability. [29 CFR 1926.452(p)(1)]
- To make swaged attachments or spliced eyes on wire suspension ropes. [29 CFR 1926.451(d)(11)]
- For Components and Design:
- To design scaffold components construction in accordance with the design. [29 CFR 1926.451(a)(6)]
The standard requires a registered professional engineer to perform the following duties in these circumstances:
- For Suspension Scaffolds:
- To design the direct connections of masons' multi-point adjustable suspension scaffolds. [29 CFR 1926.451(d)(3)(i)]
- For Design:
- To design scaffolds that are to be moved when employees are on them. [29 CFR 1926.451(f)(5)]
- To design pole scaffolds over 60 feet (18.3 m) in height. [29 CFR 1926.452(a)(10)]
- To design tube and coupler scaffolds over 125 feet (38 m) in height. [29 CFR 1926.452(b)(10)]
- To design fabricated frame scaffolds over 125 feet (38 m) in height above their base plates. [29 CFR 1926.452(c)(6)]
- To design brackets on fabricated frame scaffolds used to support cantilevered loads in addition to workers. [29 CFR 1926.452(c)(5)]
- To design outrigger scaffolds and scaffold components. [29 CFR 1926.452(i)(8)]
General Requirements For Scaffolds [29 CFR 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. [29 CFR 1926.451(a)(1)] A qualified person must design the scaffolds, which are loaded in accordance with that design. [29 CFR 1926.451(a)(6)] Scaffolds and scaffold components must not be loaded in excess of their maximum intended loads or rated capacities, whichever is less. [29 CFR 1926.451(f)(1)] Load carrying timber members should be a minimum of 1,500 lb-f/in2 construction grade lumber. [29 CFR 1926 Subpart L Appendix A(1)(a)]
Scaffold Platform Construction:
Each platform must be planked and decked as fully as possible with the space between the platform and uprights not more than 1 inch (2.5 cm) wide. The space must not exceed 9½ inches (24.1 cm) when side brackets or odd-shaped structures result in a wider opening between the platform and the uprights. [29 CFR 1926.451(b)(1)]
Scaffold planking must be able to support, without failure, its own weight and at least four times the intended load. [29 CFR 1926.451(a)(1)]
Solid sawn wood, fabricated planks, and fabricated platforms may be used as scaffold planks following the recommendations by the manufacturer or a lumber grading association or inspection agency. [29 CFR 1926 Subpart L Appendix A(1)(b) & (c)]
Tables showing maximum permissible spans, rated load capacity, and nominal thickness are in 29 CFR 1926 Subpart L Appendix A(1)(b) & (c) of the standard.
The platform must not deflect more than 1/60 of the span when loaded. [29 CFR 1926.451(f)(16)]
The standard prohibits work on platforms cluttered with debris. [29 CFR 1926.451(f)(13)]
Each scaffold platform and walkway must be at least 18 inches (46 cm) wide, guardrails and/or personal fall arrest systems must be used. [29 CFR 1926.451(b)(2)]
The standard requires employers to protect each employee on a scaffold more than 10 feet (3.1 m) above a lower level from falling to that lower level. [29 CFR 1926.451(g)(1)]
To ensure adequate protection, install guardrails along all open sides and ends before releasing the scaffold for use by employees, other than the erection and dismantling crews. [29 CFR 1926.451(g)(4)(i)]
Guardrails are not required, however:
- When the front end of all platforms are less than 14 inches (36 cm) from the face of the work. [29 CFR 1926.451(b)(3)]
- When outrigger scaffolds are 3 inches (8 cm) or less from the front edge. [29 CFR 1926.451(b)(3)(i)]
- When employees are plastering and lathing 18 inches (46 cm) or less from the front edge. [29 CFR 1926.451(b)(3)(ii)]
Criteria for Supported Scaffolds:
All employees must be trained by a qualified person to recognize the hazards associated with the type of scaffold being used and how to control or minimize those hazards. The training must include fall hazards, falling object hazards, electrical hazards, proper use of the scaffold, and handling of materials. [29 CFR 1926.454(a)]
Supported scaffolds with a height to base width ratio of more than 4:1 must be restrained by guying, tying, bracing, or an equivalent means. [29 CFR 1926.451(c)(1)]
Either the manufacturers' recommendation or the following placements must be used for guys, ties, and braces:
- Install guys, ties, or braces at the closest horizontal member to the 4:1 height and repeat vertically with the top restraint no further than the 4:1 height from the top.
- Vertically - every 20 feet (6.1 m) or less for scaffolds less than 3 feet (0.91 m) wide; every 26 feet (7.9 m) or less for scaffolds more than 3 feet (0.91 m) wide.
- Horizontally - at each end; at intervals not to exceed 30 feet (9.1 m) from one end. [29 CFR 1926.451(c)(1)]
Forklifts can support platforms only when the entire platform is attached to the fork and the fork-lift does not move horizontally when workers are on the platform. [29 CFR 1926.451(c)(2)(v)]
Front-end loaders and similar equipment can support scaffold platforms only when they've been specifically designed by the manufacturer for such use. [29 CFR 1926.451(c)(2)(iv)]
Also see, OSHA Standards Interpretation and Compliance Letter: 09/30/1999 - Forklifts in construction: Elevating personnel and operator training.
What materials can be used to increase the working level height of employees on supported scaffolds?
Stilts may be used on a large area scaffold. When a guardrail system is used, the guardrail height must be increased in height equal to the height of the stilts. The manufacturer must approve any alterations to the stilts. [29 CFR 1926.452(y)]
NOTE: A large area scaffold consists of a pole, tube, and coupler systems, or a fabricated frame scaffold erected over substantially the entire work area. [29 CFR 1926.450(b)]
Criteria for Suspended Scaffolds:
A suspension scaffold contains one or more platforms suspended by ropes or other non-rigid means from an overhead structure, 29 CFR 1926.450(b), such as the following scaffolds: single-point, multi-point, multi-level, two-point, adjustable, boatswain's chair, catenary, chimney hoist, continuous run, elevator false car, go-devils, interior hung, masons', and stone setters'.
Some of the requirements for all types of suspension scaffolds include:
- Employers must ensure that all employees are trained to recognize the hazards associated with the type of scaffold being used. [29 CFR 1926.454(a)]
- All support devices must rest on surfaces capable of supporting at least four times the load imposed on them by the scaffold when operating at the rated load of the hoist, or at least one-and-a-half times the load imposed on them by the scaffold at the stall capacity of the hoist, whichever is greater. [29 CFR 1926.451(d)(1)]
- A competent person must evaluate all direct connections prior to use to confirm that the supporting surfaces are able to support the imposed load. [29 CFR 1926.451(d)(3)(i)]
- All suspension scaffolds must be tied or otherwise secured to prevent them from swaying, as determined by a competent person. [29 CFR 1926.451(d)(18)]
- Guardrails, a personal fall-arrest system, or both must protect each employee more than 10 feet (3.1 m) above a lower level from falling. [29 CFR 1926.451(g)]
- A competent person must inspect ropes for defects prior to each workshift and after every occurrence that could affect a rope's integrity. [29 CFR 1926.451(d)(10)]
- When scaffold platforms are more than 24 inches (61 cm) above or below a point of access, ladders, ramps, walkways, or similar surfaces must be used. [29 CFR 1926.451(e)(1)]
- When using direct access, the surface must not be more than 24 inches (61 cm) above or 14 inches (36 cm) horizontally from the surface. [29 CFR 1926.451(e)(8)]
- When lanyards are connected to horizontal lifelines or structural members on single-point or two-point adjustable scaffolds, the scaffold must have additional independent support lines equal in number and strength to the suspension lines and have automatic locking devices. [29 CFR 1926.451(g)(3)(iii)]
- Emergency escape and rescue devices must not be used as working platforms, unless designed to function as suspension scaffolds and emergency systems. [29 CFR 1926.451(d)(19)]
Counterweights used to balance adjustable suspension scaffolds must be able to resist at least four times the tipping moment imposed by the scaffold operating at either the rated load of the hoist, or one-and-a-half (minimum) times the tipping moment imposed by the scaffold operating at the stall load of the hoist, whichever is greater. [29 CFR 1926.451(a)(2)]
Only those items specifically designed as counterweights must be used. [29 CFR 1926.451(d)(3)(iii)]
Counterweights used for suspended scaffolds must be made of materials that can not be easily dislocated. Flowable material, such as sand or water, cannot be used. [29 CFR 1926.451(d)(3)(ii)]
Counterweights must be secured by mechanical means to the outrigger beams. [29 CFR 1926.451(d)(3)(iv)]
Vertical lifelines must not be fastened to counterweights. [29 CFR 1926.451(g)(3)(i)]
Where do tiebacks for outrigger beams, cornice hooks, roof hooks, roof irons, parapet clamps, or similar devices need to be secured?
A single tieback must be installed perpendicular to the face of the building or structure. Two tie-backs installed at opposing angles are required when a perpendicular tieback cannot be installed. [29 CFR 1926.451(d)(3)(x)]
The suspension ropes must be long enough to allow the scaffold to be lowered to the level below without the rope passing through the hoist, or the end of the rope configured to prevent the end from passing through the hoist. [29 CFR 1926.451(d)(6)] Also see, OSHA Standards and Interpretation Letter: 06/16/1999 - Scaffolds: Lifelines, support lines, and suspension ropes cannot have a common anchor point.
The standard prohibits using repaired wire. [29 CFR 1926.451(d)(7)]
Drum hoists must contain no less than four wraps of the rope at the lowest point. [29 CFR 1926.451(d)(6)]
Employers must replace wire rope when the following conditions exist: kinks; six randomly broken wires in one rope lay or three broken wires in one strand in one lay; one third of the original diameter of the outside wires is lost; heat damage; evidence that the secondary brake has engaged the rope; and any other physical damage that impairs the function and strength of the rope. [29 CFR 1926.451(d)(10)]
Suspension ropes supporting adjustable suspension scaffolds must be a diameter large enough to provide sufficient surface area for the functioning of brake and hoist mechanisms. [29 CFR 1926.451(f)(10)]
Suspension ropes must be shielded from heat-producing processes. [29 CFR 1926.451(f)(11)]
Power-operated hoists used to raise or lower a suspended scaffold must be tested by a qualified testing laboratory. [29 CFR 1926.451(d)(13)]
The stall load of any scaffold hoist must not exceed three times its rated load. [29 CFR 1926.451(a)(5)]
The stall load is the load at which the prime-mover (motor or engine) of a power-operated hoist stalls or the power to the prime-mover is automatically disconnected. [29 CFR 1926.450(b)]
Gasoline power-operated hoists or equipment are not permitted. [29 CFR 1926.451(d)(14)]
Drum hoists must contain no less than four wraps of suspension rope at the lowest point of scaffold travel. [29 CFR 1926.451(d)(6)]
Gears and brakes must be enclosed. [29 CFR 1926.451(d)(15)]
An automatic braking and locking device, in addition to the operating brake, must engage when a hoist makes instantaneous change in momentum or an accelerated overspeed. [29 CFR 1926.451(d)(16)]
Welding can be done from suspended scaffolds when
- a grounding conductor is connected from the scaffold to the structure and is at least the size of the welding lead.
- the grounding conductor is not attached in series with the welding process or the work piece.
- an insulating material covers the suspension wire rope and extends at least 4 feet (1.2 m) above the hoist.
- insulated protective covers cover the hoist.
- the tail line is guided, retained, or both, so that it does not become grounded.
- each suspension rope and any other independent lines are insulated from grounding. [29 CFR 1926.451(f)(17)]
What materials can be used to increase the working level height of employees on suspended scaffolds?
Employers must provide access when the scaffold platforms are more than 2 feet (0.6 m) above or below a point of access. [29 CFR 1926.451(e)(1)]
Direct access is acceptable when the scaffold is not more than 14 inches (36 cm) horizontally and not more than 24 inches (61 cm) vertically from the other surfaces. [29 CFR 1926.451(e)(8)]
The standard prohibits the use of crossbraces as a means of access. [29 CFR 1926.451(e)(1)]
Effective September 2, 1997, employees erecting and dismantling supported scaffolding must have a safe means of access provided when a competent person has determined the feasibility and analyzed the site conditions. [29 CFR 1926.451(e)]
The standard does require specific clearance distances. [29 CFR 1926.451(f)(6)]
Fall Protection Requirements:
Employers must provide fall protection for each employee on a scaffold more than 10 feet (3.1 m) above a lower level. [29 CFR 1926.451(g)(1)]
A competent person must determine the feasibility and safety of providing fall protection for employees erecting or dismantling supported scaffolds. [29 CFR 1926.451(g)(2)]
Fall protection includes guardrail systems and personal fall arrest systems. Guardrail systems are explained below in another question. A personal fall-arrest system is a system used to arrest an employee in a fall from a working level. Personal fall-arrest systems include harnesses, components of the harness/belt such as D-rings, and snap hooks, lifelines, and anchorage points.
NOTE: As of January 1, 1998, subpart M of this part provides that body belts are not acceptable as part of a personal fall arrest system. [29 CFR 1926.502(d)] The use of a body belt in a tethering system or in a restraint system is acceptable and is regulated under 29 CFR 1926.502(e). [29 CFR 1926.453(b)(2)(v) and 29 CFR 1926.451(g)(3)]
When working from an aerial lift, attach the fall-arrest system to the boom or basket. [29 CFR 1926.453(b)(2)(v)]
The following chart illustrated the type of fall protection required for specific scaffolds.
|Type of Scaffold||Fall Protection Required|
|Aerial lifts||Personal fall-arrest system|
|Boatswains' chair||Personal fall-arrest system|
|Catenary scaffold||Personal fall-arrest system|
|Personal fall-arrest system, or a guardrail system, or a ¾ inch (1.9 cm) diameter grabline or equivalent handhold securely fastened beside each crawling board|
|Float scaffold||Personal fall-arrest system|
|Ladder jack scaffold||Personal fall-arrest system|
|Needle beam scaffold||Personal fall-arrest system|
|Self-contained scaffold||Both a personal fall-arrest system and a guardrail system|
|Single-point and two-point suspension scaffolds||Both a personal fall-arrest system and a guardrail system|
|Supported scaffold||Personal fall-arrest system or guardrail system|
|All other scaffolds not specified above||Personal fall-arrest system or guardrail systems that meet the required criteria|
Personal fall arrest systems can be used on scaffolding when there are no guardrail systems. [29 CFR 1926.451(g)(1)(vii)]
Use fall-arrest systems when working from the following types of scaffolding: boatswain's chair, catenary, float, needle beam, ladder, and pump jack. [29 CFR 1926.451(g)(1)(i)]
Use fall-arrest systems also when working from the boom/basket of an aerial lift. [29 CFR 1926.453(b)(2)(v)]
Fall-arrest and guardrail systems must be used when working on single- and two-point adjustable suspension scaffolds and self-contained adjustable scaffolds that are supported by ropes. [29 CFR 1926.451(g)(1)]
Falling Object Protection
To protect employees from falling hand tools, debris, and other small objects, install toeboards, screens, guardrail systems, debris nets, catch platforms, canopy structures, or barricades. In addition, employees must wear hard hats. [29 CFR 1926.451(h)(1), 29 CFR 1926.451(h)(2) and 29 CFR 1926.451(h)(3)]
Specific Scaffold Requirements [29 CFR 1926.452]
The standard sets requirements for specific types of scaffolds. These are found in 29 CFR 1926.452, "Additional requirements applicable to specific types of scaffolds."
Aerial Lift Requirements [29 CFR 1926.453]
Vehicle-mounted aerial devices used to elevate employees - such as extensible boom platforms, aerial lifts, articulating boom platforms, and vertical towers - are considered "aerial lifts".
Some of the specific requirements include [29 CFR 1926.453(b)]:
- Only authorized personnel can operate aerial lifts.
- The manufacturer or equivalent must certify any modification.
- The insulated portion must not be altered to reduce its insulating value.
- Lift controls must be clearly marked.
- Brakes must be set and outriggers used.
- Boom and basket load limits must not be exceeded.
- Employees must wear personal fall arrest systems, with the lanyard attached to the boom or basket.
- No devices to raise the employee above the basket floor can be used.
Also see, OSHA Standards Interpretation and Compliance Letters: