Asbestos is a name given to several naturally occurring fibrous minerals. There are two main types: serpentine (chrysotile or white asbestos) and amphiboles, (including amosite/brown asbestos). Asbestos minerals are strong and, heat and chemical-resistant so they were once considered to be ideal building materials such as insulation boards, boilers, pipes and sheet roofing. Asbestos containing materials are still found in lots of places K but are now banned in new building materials.
The Public Health England website has further information and guidance about the potential health impact of asbestos exposure. More information on asbestos is also available from the Health and Safety Executive.