132 Evaluation of the Effectiveness of a New Technical Solution to Reduce Dust Emission from Road Planers

Abstract A planer equipped with a rotating cutting drum is used to remove about ten cm thick of road surfaces. This process generates dust likely to contain crystalline silica. The machine operator and people around may be particularly exposed. It is therefore essential to promote effective preventive solutions, in particular from dust collection and filtration systems, to reduce dust exposure. Tests were realized to evaluate the performance of technical devices designed to capture and filter dust emitted by road planers. The measurements were carried out on a road planer equipped with an air collection device located next to the milling drum, supplemented by an electrostatic separator to trap collected dust. The dust collection efficiency of the venting system was determined by gas tracing. The efficiency of the electrostatic separator was both evaluated in laboratory conditions (static machine) from a reference dust generated upstream of the system, and in the field during road surface planing. The tests conducted on the planer showed the effectiveness of the dust collection and filtration devices implanted on the machine and tested both in static and in the field. The capture efficiency determined by gas tracing is about 90 % and the separation efficiency of the electrostatic precipitator, determined on the static machine from test dust, is respectively 60 and 90% at aerodynamic diameters 1 and 4 μm. The average separation efficiency obtained from the measurements with the machine in real operation is 91% for respirable dust and 95% for respirable crystalline silica.