Scaffold JSA

Scaffolding fails in two different ways, and a JSA has to cover both: the people on the platform can fall off it, and the structure itself can come down. The first is a fall protection problem, the second an engineering one — capacity, foundation, ties and planking.

Scaffolds also carry their own trigger height. Fall protection on a scaffold is required above 10 feet, not the 6 feet that applies to general construction work, and the erection and dismantling crew is the most exposed group of all because they work on an incomplete structure.

What the work involves

• Preparing the foundation and setting base plates or mud sills
• Erecting, moving, altering and dismantling the scaffold
• Planking out platforms and fitting guardrails
• Working from the platform with tools and material
• Daily inspection and tagging before each shift

Hazards and controls

Controls are listed in hierarchy order — the further down the list a control sits, the less it should be carrying on its own.

1. Fall from the scaffold platform

• Engineering: guardrail systems on all open sides and ends of platforms more than 10 feet above a lower level.
• Engineering: platforms fully planked or decked, with no gaps a boot can go through.
• Administrative: a competent person determines the fall protection for the erection and dismantling crew, who work before the guardrails exist.

29 CFR 1926.451(g)(1) requires fall protection for each employee on a scaffold more than 10 feet above a lower level. 29 CFR 1926.451(b)(1) requires each platform on all working levels to be fully planked or decked.

2. Scaffold collapse under load

• Engineering: scaffold and its components capable of supporting their own weight plus four times the maximum intended load, erected to the manufacturer or a qualified person's design.
• Engineering: sound, rigid footing — base plates and mud sills, never blocks, bricks or barrels.
• Administrative: erection, alteration and dismantling under the supervision of a competent person, with ties and bracing as designed, not as convenient.

29 CFR 1926.451(a)(1) requires each scaffold and component to support its own weight and at least four times the maximum intended load. 29 CFR 1926.451(f)(7) requires scaffolds to be erected, moved, dismantled or altered only under the supervision of a competent person qualified in scaffold work.

3. Unsafe access — climbing the frame or cross braces

• Engineering: a stair tower, ladder or built-in access provided as part of the scaffold.
• Administrative: cross braces are not a ladder, and the rule holds for the erection crew too.

29 CFR 1926.451(e)(1) requires safe means of access for each employee erecting or working on a scaffold, and prohibits the use of cross braces as a means of access.

4. Contact with energized power lines during erection or moving

• Eliminate: survey for overhead lines and site the scaffold clear of them; have the utility de-energize or cover lines that cannot be cleared.
• Engineering/administrative: maintain the minimum clearance from energized lines during erection, use and movement — and remember that a scaffold being walked or rolled changes its clearance.

29 CFR 1926.451(f)(6) sets minimum clearance distances between scaffolds and energized power lines, and requires the clearance to be maintained during erection, use, movement and dismantling.

5. Material falling from the platform onto people below

• Engineering: toeboards, debris nets or screens at platform edges where material is stored.
• Administrative: barricade the area beneath; no stockpiling at the open edge; hoist material rather than hand it up.
• PPE: hard hats for everyone in the vicinity.

29 CFR 1926.451(h) requires falling object protection for employees on and below scaffolds, including toeboards, screens, debris nets or barricaded areas. 29 CFR 1926.454 requires scaffold users and erectors to be trained by a qualified person in the hazards and the procedures that control them.

A worked example row

This is how one line of the finished JSA reads, with the risk bands scored on the same 4-band matrix the generator prints:

Related work activities

• Working at Heights JSA
• Ladder Safety JSA
• Steel Erection JSA