The University of Chicago
Safety Manual
Occupational Safety and Health Programs

Scaffold Safety

Please note that this program has a glossary.  The glossary contains the definitions for various terms used in the program.  These terms are highlighted in bold print the first time they appear in the body of the program.

Policy

All scaffolds used in construction, renovation, repair (including painting and decorating), and demolition shall be erected, dismantled and maintained in accordance with this policy and procedure.  No University employee shall design any scaffolding.

Authority and Responsibility

Environmental Health and Safety is responsible for:

• Reviewing this policy to ensure compliance with current regulations;
• Reporting any questionable conditions that are discovered to the responsible department;
• Serving as the competent person; and
• Ensuring all affected employees are trained in accordance with this policy.

Departments affected by this policy are responsible for:

• Ensuring all affected employees follow the prescribed practices within this policy; and
• Designating a qualified person to design and supervise during the erection, use and disassembling of scaffolding; and
• Ensuring all inspection and maintenance practices for scaffolds are conducted by a competent person in accordance with this policy and procedure.

Employees affected by this policy are responsible for complying with the practices within the Scaffold Safety policy.

The competent person shall be trained in accordance with the Occupational Safety and Health Administration (OSHA) and responsible for:

• Directing employees who erect, dismantle, move or alter scaffolding;
• Determining if it is safe for employees to work from a scaffold during storms or high winds, and ensure that a personal fall arrest system is in place;
• Training employees involved in erecting, disassembling, moving, operating, repairing, maintaining, or inspecting scaffolding to recognize associated work hazards;
• Inspecting scaffolds and scaffold components for visible defects before each work shift, and after any occurrence which could affect the structural integrity, and to authorize prompt corrective action;
• Inspecting ropes on suspended scaffolds prior to each workshift and after every occurrence which could affect the structural integrity, and to authorize prompt corrective actions;
• For suspension scaffolds evaluating direct connections to support the load to be imposed; and
• For erectors and dismantler's, determining the feasibility and safety of providing fall protection and access.

Qualified persons shall be responsible for:

• Training employees working on the scaffolds to recognize the associated hazards and understand procedures to control or minimize those hazards; and
• For suspension scaffolds;
• Designing platforms on two-point adjustable suspension types that are less than 36 inches wide to prevent instability;
• Making swaged attachments and spliced eyes on wire suspension ropes; and
• Designing components in accordance with design specifications.

General Requirements for Scaffolds

No University employee shall design scaffolding.  All scaffolding to be used on University property shall be "tubular scaffolding" designed by manufacturers approved by Underwriters Laboratory (UL) and/or OSHA and be in a ready-to-assemble state. 

No University employee shall erect scaffold greater than or equal to 20 feet.  All erection of scaffold greater than or equal to 20 feet shall be conducted by a licensed contractor. 

Capacity/Loads

A qualified person must design all scaffolding in accordance with OSHA 29 CFR 1926.451 "General Requirements for Scaffolds” and 29 CFR 1926.452 "Additional Requirements Applicable to Specific Types of Scaffolds".

Stationary scaffolds over 125 feet in height and rolling scaffolds over 60 feet in height shall be designed by a professional engineer.  All equipment shall be inspected to see that it is in good condition and is serviceable.  Damaged or deteriorated equipment shall not be used.

All scaffolds and their components must support without failure its own weight and at least four times the maximum intended load applied or transmitted to the scaffold.

Platforms

Platforms shall be constructed as follows:

• Platforms shall be entirely planked and decked with space not more than one inch wide between the platforms and uprights;
• The platform shall not deflect more than 1/60 of the span when loaded;
• All platforms shall be kept clear of debris or other obstructions that may hinder the working clearance on the platform;
• Wood planks shall be inspected to see that there are graded for scaffold use, are sound and in good condition, straight grained, free from saw cuts, splits and holes;
• Platforms and walkways shall be at least 18 inches in width.  When the work area is less than 18 inches wide, guardrails and/or personal fall arrest systems shall be used;
• Where platforms are overlapped to create a long platform, the overlap shall occur only over supports, and shall not be less than 12 inches unless the platforms are nailed;
• A platform greater than 10 feet in length shall not extend over its support more than 18 inches, 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;
• A platform less than 10 feet in length shall shall not extend over its support more than 12 inches, 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;
• Wood surface shall not be covered with opaque finishes, other than the edges for making identification;
• Platforms may be coated periodically with wood preservatives, fire-retardant finishes, and slip-resistant finishes; however, the coating shall not obscure the top or bottom wood surfaces; and
• Each end of the platform, unless cleated or otherwise restrained by hooks or equivalent means, shall extend over the centerline of its support at least six inches.

Scaffold components manufactured by different manufacturers shall not be intermixed unless the components fit together without force and the scaffold's structural integrity is maintained.  Scaffold components made of dissimilar metals shall not be used together unless a competent person has determined that galvanic action will not reduce the strength of any component.

Guardrails

All scaffolds more than six feet above the lower level shall protect employees with guardrails on each open side of the scaffold.  Guardrails shall be installed along the open sides and ends before releasing the scaffold for use by the employees, other than erection or dismantling crews.

Guardrails are not required when:

• The front end of all platforms are less than 14 inches from the face of the work; and
• When employees are plastering and lathing 18 inches or less from the front edge.

Guardrails shall be constructed as follows:

• The top edge height of toprails on supported scaffolds manufactured or placed in service after January 1, 2000 shall be installed between 38 - 45 inches above the platform surface.  The top edge height on supported scaffolds manufactured or 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 – 45 inches;

• When midrails, screens, mesh, intermediate vertical members, solid panels, or equivalent structural members are used, they shall be installed between the top edge of the guardrail system and the scaffold platform;

• When midrails are used, they shall be installed at a height midway between the top edge of the guardrail system and the scaffold platform;

• When screens and mesh are used, they shall extend from the top edge of the guardrail system to the scaffold platform, and along the entire opening between the supports;

• When intermediate members are used, they shall not be more than 19 inches apart;

• Each toprail or equivalent member of a guardrail system shall be capable of withstanding a force of at least 100 pounds for systems on single-point adjustable suspension or two-point adjustable suspension scaffolds, and at least 200 pounds for guardrail systems installed on other scaffolds;

• When  the loads specified above are applied in a downward direction, the top edge shall not drop below the height above the platform surface required above;

• Midrails, screens, mesh, intermediate vertical members, solid panels and equivalent structural members shall be capable of withstanding a force of at least 75 pounds for systems with a minimum 100 pound toprail capacity, and at least 150 pounds for systems with a minimum 200 pound toprail capacity;

• Guardrails shall be surfaced to prevent injury to an employee from punctures or lacerations and prevent snagging of clothing;

• The ends of all rails shall not overhang the terminal posts except when such overhang does not constitute a projection hazard;

• Steel or plastic banding shall not be used as a toprail or midrail;

• Manila or plastic (or other synthetic) rope being used for toprails or midrails shall be inspected by a competent person as frequently as necessary; and

• Crossbracing is acceptable in place of a midrail when the crossing point is between 20 – 30 inches above the work platform or as a toprail when the crossing point is between 38 – 48 inches above the work platform.  The end points at each upright shall be no more than 48 inches.

Erection of Scaffolds

Prior to Erection – All Scaffold Assemblies

All jobsites and work areas shall be inspected prior to the erection of scaffolds to determine the site’s ability to support structure, and for location of electric power lines, overhead obstructions, wind conditions, and the need for overhead protection or weather protection coverings.

Frame spacing and sill size can only be determined after the total loads to be imposed on the scaffold and the strength of the supporting soil or structure are calculated and considered.  Special consideration is required when scaffolding is to be erected on fill, soft or frozen ground.  Sills shall be level and in full contact with the supporting surface. A qualified person must do this analysis.  Load carrying information on components is available from the scaffold manufacturer.

Wood planks used for platforms on scaffolding shall be specifically graded for scaffold use by an approved grading agency.  Planks are stamped for scaffold approved loading and usage on one end. 

Erection of Fixed Scaffold

Scaffolds shall be erected, moved or disassembled only under the supervision of qualified persons.

Base plates or screwjacks shall be in firm contact with both the sills and the legs of the scaffolding.  Screwjacks with base plates shall be used to compensate for uneven ground.  Do not use unstable objects such as loose bricks, blocks of wood or concrete to shore up the uneven surface.

All scaffolding shall be plumb and level.  Tying, guying, or bracing may be needed to assure a safe and stable scaffold assembly.  Do not force members to fit.  Be sure scaffolding stays level and plumb as erection progresses.  The height of the scaffold in relation to the minimum base width, wind loads, the use of brackets or cantilevered platforms and imposed scaffold load determines the need for stability bracing.

Access Requirements

Access shall be provided when scaffold platforms are more than 24 inches above or below the point of access.  Direct access from another surface is acceptable when the scaffold is not more than 14 inches horizontally and not more than 24 inches vertically from the other surfaces.  Crossbraces shall not be used as a means of access.

Type of accesses which are permitted:

• Portable ladders tied off to the structure;
• Hook-on ladders;
• Attachable ladders
• Stairways;
• Stair towers;
• Ramps and walkways; or
• Integral prefabricated frames.

When erecting or dismantling supported scaffolds, a safe means of access shall be provided when a competent person has determined the feasibility and analyzed the site conditions.

Use Requirements

The use of shore scaffolds and lean-to-scaffolds is strictly prohibited.   All employees are prohibited from working on scaffolds covered with snow, ice or other slippery materials.

Clearance Distances Between Scaffolds and Powerlines

The following table provides the clearance distances between scaffolds and powerlines, or any other conductive material, while being erected, used, dismantled, altered or moved.

EXCEPTION:  Scaffolds and materials may be closer to power lines than specified where such clearance is necessary for performance of work and only after the utility company or electrical system operator has de-energized or relocated the lines.

Scaffold Requirements

The following are the requirements for specific types of scaffolds:

• Appendix A - "Requirements for Fabricated Frame Scaffolds" (tubular welded frames scaffolds)
• Appendix B - "Requirements for Form and Carpenter's Bracket Scaffolds";
• Appendix C - "Requirements for Pump Jack Scaffolds";
• Appendix D - "Requirements for Ladder Jack Scaffolds";
• Appendix E - "Requirements for Crawling Boards" (chicken ladders)
• Appendix F - "Requirements for Two-Point Adjustable Suspension Scaffolds";
• Appendix G - "Requirements for Multi-Level Suspended Scaffolds";
• Appendix H - "Requirements for Mobile Scaffolds"; and
• Appendix I - "Requirements for Aerial Lifts".

Stilts

Employee use of stilts on scaffolds is prohibited. 

Scaffolds Prohibited for Use

The following types of scaffolds are prohibited for use on University property:

• Shore scaffolds;
• Lean-to scaffolds;
• Window jack scaffolds;
• Catenary scaffolds;
• Float scaffolds;
• Needle beam scaffolds;
• Pole scaffolds;
• Tube and coupler scaffolds;
• Plasterers, decorators and large area scaffolds;
• Horse scaffolds;
• Outrigger scaffolds;
• Interior hung scaffolds;
• Step, platform and trestle ladder scaffolds; and
• Single-point adjustable suspension scaffolds.

Fall Protection

All employees working on scaffolds six feet or more above ground/floor level shall use fall protection in accordance with the University's Safety Manual Fall Protection Program, Section 3.17.

All scaffolding shall have toeboards, screens, a guardrail system and/or debris nets as determined by a competent person.

Training

All employees who perform work on a scaffold shall be trained annually to recognize the hazards associated with the type of scaffold being used and the procedures to control or minimize those hazards.  Employees shall be trained to demonstrate competency in the following areas:

• Nature of electrical, fall hazards and falling object hazards in the work area;
• Proper use of scaffolds;
• Proper handling of materials on scaffolds;
• Proper erecting, maintaining and disassembling of fall protection systems;
• Proper construction, use, placement and care in handling of scaffolds; and
• Maximum intended load and load-carrying capacities of scaffolds used.

Section 3 Index

 Table of Contents

Environmental Health and Safety
Issued: 05/01/00
Revised: 08/01/08