Asbestos-Containing Materials 

ACMsAsbestos-Containing Materials are substances that contain asbestos. Asbestos itself is a family of fibrous silicate minerals historically used for thermal and electrical insulation. Asbestos poses a significant hazard to human health, predominantly via inhalation, where the microscopic fibres irritate the lungs and cause significant damage, including scarring (asbestosis) due to prolonged exposure.

ACMs are typically raw asbestos fibres infused within a matrix of textile fabric, cement, concrete, lagging or foam. These materials were prolifically used for insulating buildings and as lining materials in metal casting. They were also used in gaskets to create seals between pipes (ie flanges) and/or machinery. In most cases, the presence of ACMs is deemed to be safe, provided adequate steps are taken to ensure that the material is not disturbed. This can be challenging in an inspection setting, since insulating layers may need to be removed to gain access to the inspection surface.

In these instances, a risk assessment for the presence of ACMs should be considered and expert guidance sought before work is undertaken. It should be noted that employers have a responsibility to protect workers from asbestos exposure.

For more information on ACMs, see:

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