Organisation: University of Bath
Date uploaded: 13th January 2014
Date published/launched: November 2013
This study looked at whether drivers overtaking a bicyclist changed the proximities of their passes in response to the level of experience and skill signalled by the bicyclist's appearance.

Five outfits were tested, ranging from a stereotypical sport rider’s outfit, portraying high experience and skill, to a vest with ‘novice cyclist’ printed on the back, portraying low experience.
A high-visibility bicycling jacket was also used, as were two commercially available safety vests, one featuring a prominent mention of the word ‘police’ and a warning that the rider was video-recording their journey, and one modelled after a police officer’s jacket but with a letter changed so it read ‘POLITE’.
An ultrasonic distance sensor recorded the space left by vehicles passing the bicyclist on a regular commuting route. 5,690 data points fulfilled the criteria for the study and were included in the analyses. The only outfit associated with a significant change in mean passing proximities was the police/video-recording jacket. Contrary to predictions, drivers treated the sports outfit and the ‘novice cyclist’ outfit equivalently, suggesting they do not adjust overtaking proximity as a function of a rider’s perceived experience.
Notably, whilst some outfits seemed to discourage motorists from passing within 1 metre of the rider, approximately 1-2% of overtakes came within 50 cm no matter what outfit was worn. This suggests there is little riders can do, by altering their appearance, to prevent the very closest overtakes; it is suggested that infrastructural, educational or legal measures are more promising for preventing drivers from passing extremely close to bicyclists.
For more information contact:
Ian Walker, Bath University
T: 01225 383908