Powered Two-Wheelers’ Conspicuity: The Effects of Visual Context and Awareness

In the Western world, powered two-wheelers (PTWs) are only a small share of the total motorized traffic. However, they are highly over-involved in the accidents statistics (Shinar, 2007). According to the US National Highway Traffic Safety Administration’s 2008 Traffic Safety Annual Assessment (2009), motorcyclist fatalities increased dramatically in the last decade, accounting for 14 per cent of the total US traffic fatalities. Similar statistics were collected in Great Britain, where motorcycles were involved in 14 per cent of all fatal injuries although they accounted for less than 1 per cent of the vehicle population (Clarke et al., 2004). The increase in the number of PTWs (especially the heavy ones), the increase in accidents involving PTWs and the vulnerability of the riders, all together contribute to the concern for motorcyclists’ safety (Shinar, 2007). An in-depth study (MAIDS - Motorcycle Accident In-Depth Study) conducted in Europe revealed that 73 per cent of PTWs’ accidents occurred at daytime, 90 per cent of them were in clear weather conditions and 85 per cent in light to medium traffic density (ACEM, 2004). Similar findings were obtained in a study conducted in New Zealand, which showed that 64 per cent of the PTWs’ crashes occurred in daylight and 72 per cent of these crashes occurred in clear weather (Wells et al., 2004). Given the fact that a large proportion of the accidents involving PTW occurs under fairly safe and favourable environmental conditions, one must ask what are the main factors that contribute to these accidents?.