Scaffold, Cable and Deadline on a Two-Storey Plastering Job
On a two-storey house in Gampaha, the upper slab is at 3.2 m and six workers are plastering. The scaffold is built from local jak poles with 38 mm planks spanning 2.4 m between supports; one plank has a visible crack and two planks are not cleated. Guardrails exist only on the road side, and the open stairwell has no cover. A neighbour's 230 V cable passes through the scaffold with taped insulation. The afternoon monsoon wind is gusting to 40 km/h. Materials are stacked near the scaffold edge. A worker says he will not wear a harness because there is no anchor point. There is no written scaffold inspection record, although the crew has used the scaffold for three weeks. The supervisor wants plastering to continue to meet Friday's deadline. You are the carpenter leading the crew.
1. List the hazards in priority order and explain the basis for your ranking.
Read the worked answer
Ranking principle: deal first with hazards that can kill or permanently disable in the next hour, not with the most visible or the most annoying. Use severity multiplied by likelihood, and remember that one control can cover several hazards.
- Contact with the 230 V cable - taped insulation through a wet scaffold is an electrocution risk; stop work and have the supply isolated by the electricity provider or a licensed electrician. Do not move the cable yourself.
- Fall from the scaffold or stairwell - a 3.2 m fall, a cracked plank, a missing guardrail and an unguarded stairwell are fatal or disabling risks; remove the plank, cover or guard the stairwell, and add guardrails and toe boards.
- Scaffold collapse - jak poles, no inspection record, uncleated planks and materials stacked at the edge all point to instability. Check sole plates, bracing, ties and plank span; unload the edge.
- Wind and material handling - 40 km/h gusts can move sheets and planks; stop lifting and secure loose material.
- Dust and housekeeping - cement dust and offcuts are a lower immediate risk but still need masks and clearing.
The deadline does not change the ranking. The first three are stop-work items because the consequence is death or serious injury, not a delay.
2. What immediate actions will you take before any plastering continues, and how will you communicate them to the supervisor?
Read the worked answer
Immediate actions. Stop plastering and clear the upper floor. Barricade the stairwell and the scaffold access. Ask the supervisor to phone the electricity authority or a licensed electrician to isolate and reroute the cable; until then nobody touches the scaffold near it. Remove the cracked plank and any uncleated plank from service. Do not allow materials to be stored at the scaffold edge. Secure loose sheets before the wind rises.
Scaffold checks. The scaffold needs sole plates on firm ground, effective ties to the building, diagonal bracing, guardrails at about 1 m and 0.5 m, toe boards and safe ladder access. A competent person should inspect it and record the result before reuse.
Communication. Explain to the supervisor that this is a stop-work decision, not a request, and give the specific hazards and the actions needed. Put it in the site diary and send a short written message so the deadline pressure is recorded. Offer a revised sequence: move plastering to the ground floor and internal walls while the scaffold and cable are fixed. That keeps progress without exposing workers.
3. The worker refuses to wear a harness. How do you resolve this without simply disciplining him?
Read the worked answer
Treat the refusal as information. He is correct that a harness without a suitable anchor is useless and can create a false sense of safety. A harness is also not the first choice: guardrails and a working platform are preferred because they protect everyone without relying on individual behaviour.
Resolve it in this order: (1) provide a safe platform with guardrails and toe boards so harness use is not needed for normal plastering; (2) where a harness is genuinely required, install a designed anchor point or an independent lifeline rated for fall arrest, and check that the worker has a trained fit, a shock-absorbing lanyard and a rescue plan; (3) explain the hierarchy of control and ask him to help identify a practical anchor.
Do not force him to clip to a scaffold tube, a conduit or a random pole. If no proper anchor can be provided, do not assign him to that task; move him to ground-level work. Record the discussion. This approach respects a legitimate safety concern and still keeps the site moving.