Fragile Roof and Falling Materials
You are a roof cladding supervisor on a renovation of a 1970s warehouse. The existing roof is a fragile asbestos cement sheet roof with some cracked sheets. The client wants the roof overclad with new steel sheets. The roof is 12 m high at the eaves. The site has a perimeter fence but no netting. Two roofers are about to start work on the roof. The weather is dry but windy with gusts of 35 mph. The site manager tells you to get on with the job quickly because the client is pressing for completion.
1. What are the main health and safety risks, and what control measures should be in place before work starts?
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The main risks are falls from height (12 m eaves), falling materials (fragile sheets, tools), and asbestos exposure from the fragile cement sheets. Controls: 1) Avoid working on the fragile roof if possible; use safe access equipment such as mobile elevating work platforms (MEWPs) or scaffolding with guardrails and toe boards. 2) If work on the roof is unavoidable, use crawling boards and roof ladders, and ensure the roof is structurally safe. 3) Install edge protection (guardrails) and debris netting to prevent falls and falling materials. 4) Asbestos survey and risk assessment; use appropriate RPE and PPE for asbestos, and follow asbestos regulations for removal. 5) Weather: wind gusts of 35 mph may make work unsafe; monitor conditions and stop work if wind speeds exceed safe limits for the equipment. 6) Site management: ensure a safe system of work, including a permit to work if required, and supervision. 7) Consult the client and principal designer to ensure risks are managed; do not bow to pressure to work unsafely.
2. How should the team deal with the asbestos cement sheets?
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Asbestos cement sheets contain asbestos (often chrysotile or amosite). Work on them can release fibres. Before starting, an asbestos survey should identify the presence and condition. If the sheets are to be removed or disturbed, a licensed contractor may be required for some asbestos work, but for cement sheets, usually non-licensed work with controls. Controls include: wetting the sheets to suppress dust, using hand tools rather than power tools, wearing disposable coveralls and RPE (at least FFP3), double-bagging waste in asbestos-labeled bags, and disposing of at the licensed landfill. Workers need asbestos awareness training. If sheets are cracked or damaged, they should be removed carefully. Overcladding may encapsulate them, but if the existing roof is fragile, it may need to be made safe first. The HSE guidance HSG210 and CAR 2012 apply.