Abstract
Car drivers' behaviour has been analysed in relation to the presence of a noise barrier at a distance of 5 m from the right shoulderline. A before-and-after study (without an and with noise barrier) was conducted. In the vicinity of the beginning of the noise barrier the cars show a mean shift of 0. 16 m to the left in relation to their positions 100 m before: 100 m after the beginning the mean position of the cars is the same as 100 m before.