There is a risk of drowning when people work beside or above water or have to pass near or across it on their way to or from their workplace. People can also drown in other liquids such as slurries in lagoons, foodstuffs in open vats in food processing works and solutions of chemicals in factories. If people have to work over or in the vicinity of water, there must be a safe system of work, and they must be properly trained.
Demolition, dismantling and structural alteration are high-risk activities whose safe execution is complex and technical and where expertise is vital. They require careful planning and execution by contractors who are competent in the full range of demolition techniques. During demolition and dismantling, workers are injured in falls from edges and through openings and fragile surfaces. Workers and passers-by can be injured by the premature and uncontrolled collapse of structures or parts of structures and by flying debris.