In what circumstances is asbestos dangerous?
The amount of asbestos in a product does not indicate its health risk. If the asbestos fibres are enclosed or tightly bound in a compound, there is no significant health risk. One of the main problems with asbestos came from sprayed or “friable” (easily broken up) amphibole asbestos used in buildings until the 1970s.
People working in construction, maintenance or in the renovation of older buildings should be particularly careful when handling this kind of asbestos. Construction materials containing asbestos, such as insulation boards, asbestos cement, and floor and ceiling tiles, are typically very dense and do not release significant amounts of fibres under normal use. However, fibres may be released if these products are cut or damaged.
Asbestos fibre concentrations in the air in buildings are usually about the same as in the air outside, and are not a significant risk. However, levels may be higher if friable asbestos materials are disturbed.