[Occupational exposure to asbestos in removal and protective treatment of roof coverings].

In the Province of Varese several operations have been carried out in the last two years for the removal or overcovering of asbestos-cement roofings. The present study assessed the level of exposure of the operators to inhalable asbestos fibres. The concentrations of asbestos fibres were determined by optic and electronic microscope analysis: the analyses showed the presence of mixtures of chrysotile and amosite in varying proportions. The exposure levels were correlated with the work procedures. In handling materials, there is not only fibre dispersion but sometimes also the production of asbestos-cement fragments, which can release inhalable fibres several days later. In order to limit both personal and environmental risk, it is essential to observe the rules of caution and good practice.