Asbestos is a naturally occurring mineral that was widely used in the construction industry throughout the 20th century. It was prized for its insulating properties, its strength, and its resistance to heat and fire. However, it was eventually discovered that prolonged exposure to asbestos fibers could lead to a range of respiratory diseases, including asbestosis, lung cancer, and mesothelioma.

As a result, the use of asbestos in construction materials was heavily restricted in the UK in the 1980s, and fully banned in 1999. However, countless buildings still contain asbestos-containing materials (ACMs) that were installed before the ban came into effect. These materials are usually safe as long as they are left undisturbed, but they can become dangerous if they are damaged, drilled, or otherwise disturbed.