Erecting, Altering and Dismantling Intermediate Scaffolds
Sequence and stability
Erection follows a defined sequence: set out, base and sole boards, standards, ledgers, transoms, bracing, ties, then platforms and edge protection. Stability depends on the tie pattern and bracing being installed as the scaffold rises, not afterwards. Candidates must know that ties are the primary defence against overturning and that a scaffold must never be left with ties removed and no compensating measures.
Alterations
Alterations are as hazardous as erection. Any change to a completed scaffold, such as removing a guardrail for access, cutting a ledger, or adding a spur, requires assessment and often redesign. Never alter a scaffold without authority and never remove a tie to make room for a trade.
Dismantling
Dismantle in reverse order, top down, keeping ties in place until the lift below is ready to be removed. Lower components, do not drop them. Maintain edge protection for the dismantling crew, and keep the exclusion zone live until the last component is down.
Traps
- Erecting several lifts before installing ties or bracing.
- Removing a tie temporarily and never reinstating it.
- Dismantling from the bottom or dropping components to the ground.
- Altering a scaffold without checking the design or notifying the person in control.
Rule of thumb
One lift at a time: complete the platform, guardrail and ties for each lift before starting the next.
Safe Work Practices, Hazard Control and Load Security
Hierarchy of control in practice
Apply the hierarchy of control to scaffold work: eliminate the need to work at height where possible, then use passive measures such as guardrails and toe boards, then administrative controls, and finally personal protective equipment including fall-arrest systems. Candidates must know when a harness is appropriate, how anchor points are rated, and why a harness is a last line of defence, not a substitute for guardrails.
Load security
Platforms must be fully decked, secured against movement, and rated for the load placed on them. Materials should be distributed and stacked so they do not overload a bay or create a trip hazard. Never bridge a gap with an unsecured plank or use a guardrail as a material support.
Everyday hazards
Manage dropped objects with toe boards, netting and tool lanyards; control manual handling with hoists and team lifts; and manage electrical, weather and public-protection risks. Stop work in high winds or when lightning is near, and secure loose sheeting.
Traps
- Treating a harness as equivalent to a guardrail.
- Overloading one bay by concentrating materials near the access point.
- Using unsecured planks to bridge gaps.
- Continuing work in wind conditions above the design or manufacturer limit.
Rule of thumb
If a control depends on a person remembering to clip on, look for a higher-order control first.