Asbestos removal work on roofs needs to include awareness of the risk of fall hazards for workers, as asbestos cement can become brittle with age. If you encounter any lichen on roof sheeting, be careful in the use of water and in your choice of workers’ footwear because lichen can be dangerously slippery.
Due to the potential for damage to the asbestos cement which in turn can cause fibre release, angle grinders should not be used. You can avoid damage to the sheeting by using an oxy torch or another suitable tool to remove anchoring screws and bolts.
If actually walking on the roof to remove roof sheeting then prior to removal you should spray the asbestos sheets with a PVA solution, waiting for it to dry first before removal so that it is not a slip hazard. After removal, spray the underside of the asbestos cement with the same PVA solution or with water.
If you are lowering the removed asbestos product to the ground, be careful to keep generation of respirable dust to a minimum. Ramps, chutes and similar gravity dependent devices are risky in this regard. Safer lowering methods for roof sheeting include:
- Over short distances, lowering by hand
- Using a cradle
- Using scissor lifts or similar machines
- Using stable scaffolding.
Use a full decontamination unit if the area to be removed is greater than the size of typical house or where you think that substantial dust will be loosened. When finished make sure that a clearance certificate has been issued before anyone reoccupies the area.