Workers involved in the removal of asbestos run the risk of exposure to asbestos fibres. Asbestos is only a risk if there is the potential for people to be exposed to fibres of a specific geometry that may lodge within the lining of their lungs.
Workers at risk can be comprised of two Similar Exposure Groups (SEGs) for air monitoring purposes: People removing the asbestos within the removal area; and, people outside the work area within the work site.
Monitoring of workers removing bonded asbestos may not be necessary as they will generally be aware of the risks and control measures required such as respirators. Exposure monitoring using personal monitors must be undertaken within the workers’ breathing zone during removal of different types and forms of asbestos. Other areas may be required to be monitored and will depend on the extent and nature of the removal works, including whether the material is bonded or friable. Monitoring may be required within decontamination units and around enclosures.
Placing static monitors to the boundary of the removal area can help determine if there are effective control measures in place to limit potential exposure to people outside the removal area. Exposure monitoring by sampling the air within a person's breathing zone may be conducted to alleviate an individual's concerns.
Asbestos air sampling is commonly conducted by the process outlined within the guidance note on the membrane filter method for estimating airborne asbestos fibres by the National Occupational Health & Safety Commission. The method involves sampling a known quantity of air though a filter, and assessing the fibre’s impact on the filter, whereby analysis of the filter can determine the number of fibres identified, and a concentration of fibres per millilitre can be compared against the exposure standard.
Asbestos Check provides commercial and domestic clients with extensive asbestos inspection services including asbestos identification, testing, inspection and management.
