The report points to the need for road design to take account of the psychological factors of drivers, not just the dynamic characteristics of vehicles. The following measures are recommended: (1) to decrease speed of traffic flow by (a) using traffic signs particularly if they give information rather than just a speed limit. (b) changing carriageway width or channelisation by trees. (c) introducing transverse lines on the carriageway with decreasing distance between them. (d) influencing on drivers other senses e.g. by rumble strips. 2. To increase the speed and decrease fluctuation by means of (a) smooth spatial alignment (b) visual guidance (c) increased perceived width. Avoidance of abrupt changes in speed is important and by good design an increase in speed can go with a decrease in accidents.
Abstract