Steel-toe boots (also known as safety toe boots, steel-cappe boots or safety boots) are durable boots or shoes that have a protective reinforcement in the toe, usually combined with a sole plate, which protect the foot from falling objects and punctures from below. Traditionally made of steel, the reinforcement can also be made of a composite material, or a plastic such as thermal polyurethane (TPU). Steel-toe boots are important in the construction industry and in many industrial settings. Occupational safety and health legislation or insurance requirements may require the use of such boots in some settings, and may mandate certification of such boots and the display of such certification directly on the boots. In Canada, certified boots have a Canadian Standards Association green triangle on them.