Abstract
One conventional sign was replaced by a diagrammatic one in order to determine the effect of the new sign on driver behaviour. Before and after phases of the study the effects of the sign are evaluated in terms of erratic manoeuvres of the merging traffic. It was concluded that diagrammatic signs can be initially confusing from lack of familiarity, but driver interviews were favourable. Furthermore, it was found that with the new sign weaving decreased, the driver behaviour was more consistent, and no accidents took place during the four month study period.