Supplematary material for "Enhancing cyclist safety in the EU: A study on lateral overtaking distance across seven scenarios using lab and crowdsourced methods"

Cyclists face significant risks from vehicles that overtake too closely. Through crowdsourcing (N = 200) and driving simulator (N = 20) experiments, this study examines driver behaviour in seven scenarios: laser projection, road sign, road marking, car projection, centre line and side line markings (baseline), cycle lane and no road markings. Crowdsourced participants consistently underestimated overtaking distances, particularly at wider gaps, despite feeling safer with greater distances. The simulation results showed that drivers maintained an average passing distance of 3.4 m when not constrained by traffic, exceeding the 1.5 m law of the European Union. However, interventions varied in effectiveness: while laser projection was preferred, it did not significantly increase passing distance. In contrast, a dedicated cycle lane and a solid centreline led to the greatest improvements. These findings highlight the discrepancies between perceived and actual safety and provide insight for policy interventions to enhance cyclist protection in the EU.

骑行者极易因车辆近距离超车而面临显著安全风险。本研究通过众包（N=200）与驾驶模拟器（N=20）实验，对七种场景下的驾驶员行为展开考察：激光投影、道路标识、道路标线、车辆投影、中心线与侧标线（基准组）、专用自行车道，以及无道路标线。众包参与者始终低估了超车间距，尤其在间隙较大的场景中，尽管他们认为更大的间距会带来更高的安全感。驾驶模拟器实验结果显示，在无交通约束的情况下，驾驶员的平均超车间距为3.4米，超出欧盟1.5米的法定标准。不过各类干预措施的效果存在差异：尽管激光投影方案最受青睐，但它并未显著提升超车间距。与之相对，专用自行车道与实线中心线措施带来的改善效果最为显著。本研究结果揭示了感知安全与实际安全之间的差异，并为欧盟范围内提升骑行者安全保护的政策干预提供了决策参考。