Last quarter we highlighted decramastic roofing materials, a pressed steel coated with a bitumen emulsion, known as mastic, with the asbestos located in the mastic used to adhere the stone chip to the metal.
Asbestos containing mastics, bitumen’s, sealants and other similar type products were used in many other ways and locations. The construction and building industry use adhesives and sealants for all types of permanent installation works and it was common to mix asbestos fibres into natural and synthetic glues, caulking pastes and mastics to improve durability and fire resistance. They can be found in residential, commercial and industrial buildings, and range from homogenous to non-homogenous products, commercially and hand mixed. These products are not always obvious or easily detected, and maybe side by side with negative products which look the same, or used in one location but not the neighbouring. In residential properties they can be found in many places including wall expansions and concrete slab joins, near door and window frames, as seals for drain and toilet waste pipes and around nails and gutter fixings on roofs.
Results: between July 20 and June 21 almost 1500 samples described as other mastic type materials were analysed. Of these 20% returned positive for the presence of asbestos, and of those positives 95% contained Chrysotile asbestos.
The windows below are from the same building, and contained different locations of positive mastic in the window construction.