SIZE DISTRIBUTIONS OF OCCUPATIONAL AIRBORNE ASBESTOS TEXTILE FIBRES AS DETERMINED BY TRANSMISSION ELECTRON MICROSCOPY

Publisher Website
Google Scholar
Abstract
The size distributions of airborne chrysotile fibres, associated with the processes of carding, spinning and weaving in an asbestos textile factory, have been evaluated by transmission electron microscopy. The distributions were approximately log-normal, with little change between processes. Median lengths and diameters were 1.6 and 0.08 μm, respectively. The results indicate that about 60% of fibres would not be seen by scanning electron microscopy, under the usual conditions, and an even larger proportion would be missed by optical microscopy. For fibres longer than 5 μm, then, about 70% of fibres would be seen by the scanning electron microscope. An optical microscope with a resolution of 0.3 μm would see approximately one quarter of all fibres greater than this length.