THE USE OF A NEW STATIC DEVICE BASED ON THE COLLECTION OF THE THORACIC FRACTION FOR THE ASSESSMENT OF THE AIRBORNE CONCENTRATION OF ASBESTOS FIBRES BY TRANSMISSION ELECTRON MICROSCOPY

摘要

A new static device, the CATHIA sampling head, based on the collection of the thoracic fraction is proposed for the assessment of the airborne concentration of asbestos fibres by transmission electron microscopy. By comparison with a standard aerosol sampling head, it has been shown that this sampler reduces the total mass concentration, but does not introduce any change in the most common index used to characterize an asbestos aerosol fibre, that is the concentration of fibres with length greater than 5 μm, diameter less than 3 μm and length to diameter ratio greater than 3. The homogeneity of the deposited dust on the collection filter favours the use of this sampling head with both the indirect and direct preparation methods.