Cycling safe and sound : the impact of quiet electric cars, listening to music and conversing on the phone on cyclists’ auditory perception and cycling safety. Proefschrift Technische Universiteit Delft TUD.

Cycling safety is a major traffic safety issue both in the Netherlands and abroad. The number of cyclist fatalities in the EU has been decreasing in recent years, however at a slower rate than those of car occupants or pedestrians. In the Netherlands, 20% of road fatalities and 63% of seriously injured crash victims in 2015 were cyclists. One of the factors negatively influencing cycling safety may be related to limitations on avail- ability of auditory cues. Auditory cues, such as tire and engine noises can provide important information about the presence and location of approaching traffic. Cyclists may benefit from auditory cues especially when visual information is less available, for example due to low visibility or obstructed view. Recently two trends have raised concerns about the use of auditory cues by cyclists. One is the growing popularity of electronic devices, mainly mobile phones, which are used by cyclists to listen to music or to have a conversation. The other trend concerns the increasing number of (hybrid) electric cars, which are generally quieter than conventional cars. This thesis addresses the concerns regarding the two trends and focuses on the following research questions: 1. To what extent does listening to music and conversing on the phone impact cyclists’ auditory perception and safety? 2. To what extent do acoustic properties of (hybrid) electric cars pose a safety hazard for cyclists? Cyclists in three age groups are the focus of this thesis: teenagers (aged 16-18), adults (aged 30-40) and older adults (aged 65-70). The teenagers and older adults are the main focus, as these age groups are particularly vulnerable in terms of cycling safety. Teenagers and older adults are also of interest from the perspective of the auditory perception of traffic sounds: teenagers due their frequent use of electronic devices; older adults due to age-related decline in hearing abilities. Cyclists in middle adulthood (30-40 years old) have been included to serve as a reference for the other two age groups.