[Morphologic studies of asbestos-cement surfaces].

A scanning electron microscopic procedure was used for the investigation of asbestos-cement surfaces. The samples of uncoated asbestos-cement sheets were up to 50 years old, coated asbestos-cement materials were 16 years old in maximum. Our results demonstrate that suitable coating systems effectively protect the asbestos-cement surface. On the other hand uncoated asbestos-cement shows a release of asbestos fibres locked up in cement. Therefore uncoated asbestos-cement sheets are emission sources of asbestos fibres. Wether the weathered material coursed a increase of asbestos fibre concentration in ambient air will be a subject of further investigations.