Asbestos is a fibrous material used in insulation and fireproofing that becomes friable with age, causing a range of debilitating respiratory conditions such as mesothelioma, asbestosis and lung cancer. Asbestos removalists are licensed to handle asbestos material and asbestos-contaminated dust or debris in accordance with Workplace Health and Safety regulations. The asbestos removal process typically involves the construction of a building enclosure zone and the installation of an extraction fan to create a negative air pressure and prevent the escape of airborne asbestos fibres. Demolition or removal of asbestos structures is then carried out, after which contaminated materials are safely packaged for proper disposal at a licenced waste management facility. Air monitoring is carried out throughout the asbestos removal process to assist in assessing exposures and the effectiveness of control measures.