Evaluation of Perceptual Countermeasure Treatments

Perceptual countermeasures is a term given to a class of road treatments which are intended to induce drivers to reduce travel speeds by altering driver perception of speed, risk or comfort. They are generally low cost treatments which rely on painted markings or other forms of delineation.

ARRB Transport Research, in conjunction with the Monash University Accident Research Centre (MUARC), is currently trialing two perceptual countermeasure treatments for the Australian Transport Safety Bureau (ATSB) in association with the Roads and Traffic Authority of NSW and VicRoads. The trials mark the final of a four phase project investigating perceptual countermeasure treatments and their applicability in Australia. Based on the findings of a comprehensive literature review and simulation studies, two perceptual countermeasure treatments were selected for trial. The first treatment consists of enhanced lateral guide post spacing with ascending heights around a curve. The second treatment is a peripheral transverse line (occurring on the edges but not in the centre of the travelling lane), placed at regular intervals over 400m on the approach to an intersection. Each treatment is currently being trialed in Victoria and New South Wales. In Victoria, the treatments are also being investigated during night time driving conditions.

The present paper outlines the key findings of the first three stages, and how they have input into the design and conduct of the fourth and final stage, currently in progress. It reports the progress of the fourth stage and discusses the implications of the investigation for road safety in Australia.