Effects of a painted median on lateral position and speed. A comparison between two treatments on E6 in Norway

This study investigated the effects on driver behaviour of 1 m wide painted medians on driver behaviour on 10 m wide two-lane rural roads. Two types of painted medians were studied. The first consists of transverse 1m-long green lines with 1.5 m distance between them. The second consists of two longitudinal lines 1 m apart. Valid speed data were available only for the latter treatment, where a speed decrease of 2.7 km/h was found. Both types of painted medians resulted in increased separation between opposing traffic streams. The increase varied from 60 to 72 cm, compared to a conventional centreline. It is concluded that on low-volume roads visual road modifications may represent a cost-effective alternative to physical median barriers.