Pilot measurements of asbestos exposure in road construction - Applicationof unbonded mineral products from quarries covered by the German TRGS 954

Certain rock deposits mined for in Germany may contain asbestos. In accorda nce with TRGS 954 the material is not subject to any restrictions as to its placing on the marker and use. Nevertheless, the emission of asbestos fibr es cannot be excluded, even if the mass content limit of 0.1 % is observed. Pilot measurements were conducted to describe the exposure conditions occu rring during the application of crushed stone in road construction and to d evelop a suitable measuring strategy. It could be shown that measurements o n simulated road construction sites in a quarry are not suited to yield exp osure results which are comparable to those from a real road construction s ite. Asbestos fibre concentrations determined for the latter were sometimes clearly below the detection limit of the measuring procedure. In the major ity of cases, individual measurements did not reveal any asbestos fibres at all. Asbestos concentrations determined in the quarry during material load ing are therefore unlikely to be exceeded during material application on th e construction site.