Imaging based dust sensors: equipment and methods

Dust detection and control in real time, represent one of the most challenging problem in all those environments where fine and ultra-fine airborne particulate solids products are present. Independently from the causes generating dust, airborne contaminants are an occupational problem of increasing interest as they are related to a wide number of diseases. In particular, airborne dusts are well known to be associated with several classical occupational lung diseases, such as the pneumoconiosis. Nowadays there is also an increasing interest in other dust related diseases, from the most serious as cancer and asthma, to those related with allergies or irritation and other illnesses, also occurring at lower levels of exposure. The more severe are the environmental conditions, in terms of dust presence, quantity and quality (i.e. composition. and size class distribution) more difficult is to utilize efficient sampling/detection devices: they, in fact. tend to become "blind" as dust presence increases. On the other hand severe dust production condition is exactly the case where control strategies have to be applied to realize safer conditions for the workers. In this paper the possibility to utilize a new logic to perform an "on-line" airborne dust sampling and analysis utilizing imaging is described. All the logic and the resulting operative conditions have been set-up with reference to dusts analysis in a duct after caption and before abatement. The study was then finalized to evaluate the possibility to use the new analytical procedure to realize an "on-line" monitoring and environmental control inside an aspirating cabin.