Abstract
It immediately follows from the definition of discontinuities that some thought must be devoted to the consequences of their presence with regard to the lighting-arrangements to be made for the road system, because in the first place the road user must be warned in good time that he is approaching point where the flow of traffic is changed or obstructed, and in the second place he requires more visual information at the discontinuity, so that he can take the correct measures necessitated by the change or obstruction.