Accident studies indicate that the poor conspicuity of the cyclist is an important factor in accident causation. The visibility of various conspicuity aids was evaluated during daytime using a peripheral vision detection task. The aids were also tested on public roads by measuring the gaps left by vehicles overtaking a test cyclist. An ultrasonic ranging device was used for this purpose which automatically recorded passing distances. Visibility tests were carried out at night to find a conspicuous retro-reflective treatment for a cycling jacket. The results were used in making a jacket which was tested on public roads using the gap measuring technique. It is concluded that for improving daytime conspicuity a jacket is preferable to other clothing items tested. For maximum effectiveness the material should be as bright as possible and have a highly saturated colour. At night a 35 mm wide strip of high performance retro-reflective material attached to the full width of jacket was readily seen at an adequate distance by drivers viewing under glare conditions. Approximately 10 per cent of cyclists wear high visibility clothing. To encourage greater use such clothing should be attractively styled and be comfortable to wear as well as retailing at a reasonable price. (Author/publisher)
Abstract