A new study by the University of Bath and Brunel University has concluded that it makes little difference what clothing a cyclist may wear to boost their visibility, between one and two per cent of motorists will still pass dangerously close.
Over a lengthy period, Dr Ian Gerrard from Brunel University used an ultrasonic distance recorder to measure the distance at which 5,690 vehicles passed during daylight hours. On each trip Gerrard, a regular cyclist, would choose at random a different set of attire, from 'professional' looking cycling gear, plain clothes, hi-vis gear and even a vest telling the driver of a camera mounted to the cyclist. It was expected that drivers would give a visibly more experienced looking cyclist less room that one displaying signs of being a novice, though the results didn't reflect this.
The results instead found that only the vest that warned of video recording equipment made any difference to the amount of space given, though this was just a small increase. Recordings of dangerous overtakes, i.e. those under 50cm in distance, showed no difference between outfits, with each showing around 1-2% of overtakes to be extremely close.
A similar study conducted by the Transport Research Laboratory in 1979 found that the average pass distance then was 179 cm. In this study the average was just 118cm. In the years since that first study cars have typically got wider and traffic levels increased.
Dr Ian Walker commented on the study saying: "“Many people have theories to say that cyclists can make themselves safer if they wear this or that. Our study suggests that, no matter what you wear, it will do nothing to prevent a small minority of people from getting dangerously close when they overtake you.
“This means the solution to stopping cyclists being hurt by overtaking vehicles has to lie outside the cyclist. We can’t make cycling safer by telling cyclists what they should wear. Rather, we should be creating safer spaces for cycling – perhaps by building high-quality separate cycle paths, by encouraging gentler roads with less stop-start traffic, or by making drivers more aware of how it feels to cycle on our roads and the consequences of impatient overtaking.”
In 2007 Walker used similar recording equipment to show that men and women are treated differently by the passing motorist, a fact since confirmed by researchers in the USA and Taiwan. Walkers analysis also showed that longer vehicles such as coaches and HGVs pass closer on average.
The study did not look at whether or not high-vis garments make cyclists more visible at junctions at night.
A full paper is soon to be published in the journal Accident Analysis and Prevention.