OSHA: Commercial Scaffolds. Flashcards
- How do we know a scaffold is square?
Horizontal and vertical members form right angles where they connect.
- A supported scaffold must have these features?
- Safe foundation.
- Plumb, level, square.
- Braced and solidly connected.
- Safe access.
- Safe platform.
- Guardrails: toprails, midrrails, toeboards.
- What is a brace?
A brace holds one scaffold member in a fixed position in relation to another. Bracing works horizontally or diagonally to reduce movement.
- Types of scaffold braces?
- Cross brace - diagonal in vertical plane.
2. Diagonal brace - in horizontal plane.
- When does OSHA requires braces on scaffolds?
On all supported scaffolds.
- What is a tie-in in scaffolding?
The anchor bolt tie-in is a common tie-in that support scaffold to a nearly permanent structure. It consist of a steel plate welded to a tie -in tube and drilled to receive the
Anchor bolt. The anchor bolt must be the uniformly expanding type to prevent loosening due to the longitudinal vibration of the scaffold.
- What are the requirements for a suspension scaffold?
- Be solidly attached to the structure it hangs from.
- Have all its parts in good repair.
- Have guardrails - toprails, midrails, mesh, and toeboards.
- Have a platform at least 20” wide, but no wider than 36.
- Be evaluated by a competent person before use.
- Have its wire ropes inspected daily by a competent person.
- How are suspension scaffolds hung?
- An outrigger beam with counterweights.
- A rolling outrigger beam with counterweights.
- Roof hooks.
- Parapet clamps.
- What does a suspension scaffold hung require?
Tiebacks - rod or rope - which act as secondary anchorage points to prevent movement in the scaffold.
- What must suspension scaffold hung devises be capable of support?
At least 4 times the load imposed on them by the scaffold operating at the rated load of the hoist or at least 1.5 times the load imposed by the scaffold at the stall capacity of the hoist, whichever is greater.
- How must counterweights be made?
Not of sand, liquid, or building materials.
- How must roof hooks of suspension scaffold be?
Mild steel of proper design.
- How must tiebacks of suspension scaffold be?
3/4” manila rope, or equivalent. Tieback must be installed at right angles to the face on a structurally sound structure.
- What are suspension scaffolds suspended by?
Wire, synthetic, or fiber rope.
- Ho must the suspension scaffold rope be?
They must be able to support 6 times the intended load. They must be free of corrosion and chemical damage. They must not be frayed, kinked, or have broken wires.
- How must all other than the ropes scaffolds parts support the intended load?
4 times the maximum intended load.
- How must suspension scaffolds be inspected?
By competent person before installation and during use.
- What is the difference in fall protection requirements in suspension scaffolds?
- The height of the guardrail can range from 36” to 42”.
- Workers must also wear personal fall protection. The lifeline must be securely attached to substantial members of the structure.
- What are the platform requirements for suspension scaffolds?
- They must be between 20” and 36” wide overall.
- They can be one of four types:
A. Plank-type,
B. beam-type.
C. Light metal type.
D. Ladder-type, which is rarely used.
- What is the maximum intended load for scaffold?
It is the heaviest load the scaffold is designed to carry. It is the scaffold’s live load - all workers, tools, and materials.