Tracer tests in laboratory columns have been widely used, both in saturated and unsaturated conditions, to study the infiltration in soil and subsoil. The columns used for laboratory research, during the years, varies in dimensions and characteristics but in literature, it is possible to find very few studies in which laboratory lysimeters are used. In this thesis, laboratory tracer tests have been performed at three different scales (small and intermediate column, and laboratory lysimeter). In the small scale, saturated and unsaturated tests have been performed while, with the intermediate column and the lysimeter, only unsaturated tests have been done. The main aim was to investigate the differences between the scales in terms of operating conditions, dispersivity value and hydraulic conductivity.