Alteration of a Completed Scaffold by Another Trade
A 10 m high scaffold has been handed over with a handover certificate for medium duty, fully decked, with guardrails and toe boards on all lifts. Two days later you notice that an electrician has removed the guardrail and toe board from one 2.4 m bay on the third lift to run cable tray, and has stacked six cable drums (about 40 kg each) on the fourth lift deck. The electrician says the supervisor approved it verbally. The handover certificate is still displayed at the access point, and other trades are working on the scaffold. The scaffold tag has not been changed. Your inspection is due today.
1. Explain the compliance and safety significance of what has occurred and your immediate actions.
Read the worked answer
The scaffold no longer matches its handover certificate, so the certificate is now misleading and must be withdrawn or amended. Removing guardrail and toe board creates an unguarded fall edge on the third lift, and the missing toe board allows material to fall to the level below. The cable drums add load to the fourth lift; six at about 40 kg is 240 kg concentrated in one bay, which may exceed the medium-duty rating for that deck area and must be checked against the duty and the design's point-load limits. A verbal approval from a supervisor is not a design change and does not authorise altering a handed-over scaffold. Immediate actions: stop work in the affected bays, barricade and tag the scaffold as incomplete or restricted, remove or secure the drums, and restore the guardrail and toe board or have them restored by a competent person. Notify the principal contractor and the electrician's supervisor in writing, and re-inspect before reissuing the certificate.
2. Describe how you would manage the alteration properly and prevent recurrence.
Read the worked answer
Any alteration to a handed-over scaffold must go through a change control process: the request is assessed against the design, the duty rating and the load limits, and the alteration is erected by a competent scaffolder, inspected and recorded before the certificate is reissued. For the cable tray, the correct approach is to design a penetration or a purpose-made support that does not remove guardrail; if a rail must be temporarily removed, provide equivalent protection and a documented temporary condition with a time limit. For the drums, confirm the deck's load capacity and distribute or relocate them, or provide a designated material storage area. Prevention: brief all trades at induction that the scaffold is not to be altered, label the scaffold with the duty and 'no alteration' contact, and require a permit for any change. Update the tag and certificate whenever the status changes, and include the alteration check in daily inspections.