Extended Abstract Allen et al. Proceedings of the 2016 Australasian Road Safety Conference 6 – 8 September, Canberra, Australia Do motorcyclists have greater exposure to situations in which another driver fails to give way? Trevor Allen a , Stuart Newstead a , Mark Symmons b , Michael Lenné a , Rod McClure c , Peter Hillard a , Lesley Day d a Monash University Accident Research Centre; b Faculty of Education, Monash University; c Harvard Injury Control Research Center, Harvard School of Public Health, United States; d Monash Injury Research Institute, Monash University, Victoria, Australia Abstract This study investigated the possible increased exposure of motorcyclists to situations in which another driver is more likely to fail to give way. Leading and trailing time gaps for passing motorcycles compared to those for other vehicles were measured at 178 urban and rural sites in Victoria, and categorised into 4 distinct time periods. Motorcyclists significantly more frequently had larger time gaps around them compared to other vehicles. This in turn may mean that motorcyclists are more exposed to scenarios where another driver fails to give way to them as the approaching vehicle. Background One of the most common scenarios for motorcycle injury crashes involves another driver failing to give way to the motorcyclist (Allen et al., 2013; Brown et al., 2015; Pai, 2011). There is also evidence that motorcyclists are over-represented (as the “through vehicle”) in these crash types (de Craen, Doumen, & van Norden, 2014; SWOV, 2010). Previous research has explored a number of explanations, including differences in physical or sensory conspicuity of motorcyclists (Wells et al., 2004), cognitive conspicuity factors (Beanland, Lenne, & Underwood, 2014; Olson, 1989), motorcyclist speed (Clabaux et al., 2012), and crash risk or driver responses such as look-but-fail- to-see (LBFTS) errors. However, one potential contributing factor not yet investigated is a greater exposure of motorcyclists to scenarios where driver error (related to failing to give way) is more likely. This includes circumstances where the approaching traffic is a single vehicle well clear of other vehicles travelling in the same direction. The purpose of this study was therefore to test this hypothesis, by comparing time gaps around passing motorcyclists to that of other vehicles at selected road sites in Victoria, Australia. Methods The study population were motorcycles and other vehicles observed on public roads within a 150km radius of the city of Melbourne, Australia. The data was collected as part of a larger case-control study of serious non-fatal motorcycle crashes. A motorcycle was defined as a powered two wheeler (PTW) vehicle registerable for use on Victorian roads, including mopeds and scooters. The study was approved by the Monash University Human Research Ethics Committee. Measurement of time gap for both motorycles and other vehicles was available from 178 of 204 sites sampled (87%), with a total of 101,224 vehicles (0.5% motorcycles) assessed. Sites were selected based on the location of a recent motorcycle injury crash occurring between the hours of 6am and midnight from May 2012 to August 2014. Traffic observations and measurements were sampled for a mean of 2 hours at each site on the same type-of-day (weekday, Saturday or Sunday), within 1 hour each side of the crash time. Time gap between vehicles was recorded using a traffic counter radar (Sierzega SR4, Sierzega Elektronik GmbH,Thening, Austria). The device measured time gap between passing vehicles, as well as vehicle speeds and lengths. Vehicle length allowed identification of motorcycles from other