SAFETY ISSUES WHEN DRIVERS OVERTAKE BICYCLISTS: OVERTAKING PROXIMITIES, VEHICLE TYPE, HELMET USE, AND BICYCLIST'S DISTANCE-TO-KERB

大多数人的旅程都不超过2或3英里。骑自行车通常是最快的，但人们通常开车。人们失去了宝贵的锻炼机会，在我们的城镇和城市造成了大量不必要的污染，并在碰撞中相互死亡。人们不再骑自行车是因为他们害怕被车撞。在英国，每年至少有100名骑自行车的人死于车祸，2000多人受重伤。这里提出的研究旨在减少骑自行车的人发生此类事故的可能性，这将鼓励更多的人骑自行车。汽车和自行车经常在十字路口相撞。然而，当汽车超车时也会发生碰撞，这种情况很严重，因为被超车撞到是对骑自行车的人来说最糟糕的事情之一。如果我们了解是什么决定了司机在超车时与骑自行车的人之间的距离，我们就可以做些什么来减少碰撞的可能性，要么改变道路的建设方式，要么更有可能的是，给骑自行车的人建议他们应该如何骑行。目前关于决定车手超车距离的因素有三大想法，我们计划对它们全部进行测试。第一个想法是，司机在超车时留下的距离与骑车人与自己和道路边缘之间的距离有关。换句话说，许多骑自行车的人相信，如果他们在远离路边的地方骑车，司机在超车时就会留出更多的空间，让骑自行车的人更安全。我们知道很多骑自行车的人都依赖这个想法来保证他们的安全，但它从未经过适当的测试，我们所拥有的只是许多基于人们经验的不科学报告。这个想法迫切需要适当的测试。我们计划在一辆自行车上安装一个距离传感器，将其输入电脑。这将记录每辆车经过自行车时的距离。电脑还会从摄像机和麦克风中获取信息（这样我们以后就能看到超车的车辆是什么了），这样骑自行车的人就可以记录其他有用的信息，比如人们超车时发生了什么。通过在一系列的道路上骑自行车，我们可以直接测试到自行车左边的距离会影响司机超车时留下的空间。我们还可以看到，真正重要的不是骑车人左边的空间，而是道路或车道的宽度。这辆仪表自行车也允许我们测试我们感兴趣的另外两个想法。首先，一些车辆——尤其是公共汽车——会以比其他车辆更危险的方式超车。我们怀疑这一点，因为我们最近对近5000名骑自行车的人进行了一项调查，询问他们发生过的任何事故。我们发现，涉及公共汽车的事故与其他碰撞事故不同，因为它们几乎都是在公共汽车超车时发生的。因此，我们非常想知道在这项研究中，公交车超车是否有显著的不同。我们希望做的最后一件事是让骑手有一半的时间戴头盔，一半的时间不戴头盔。许多有经验的骑手报告说，如果骑自行车的人戴着头盔，司机在骑自行车的人身边会更粗心。如果这是真的，那就意味着戴头盔实际上可能会产生与预期相反的效果，并使佩戴者处于更大的危险之中。因此，观察骑车者戴头盔时司机是否会比不戴头盔时更倾向于超车，将是一件非常有趣的事情。这项研究的结果将广泛分发给有关各方。无论结果如何，对指导道路安全活动都是非常有价值的。因此，我们将通知地方和国家政府以及其他道路安全组织（例如，BRAKE, RoSPA）和对骑车人安全感兴趣的组织（CTC， LCC等）。

Most of the journeys people make are less than 2 or 3 miles long. These would usually be fastest by bicycle, but people drive more often than not. People are missing an opportunity for valuable exercise, are causing tremendous amounts of unnecessary pollution in our towns and cities, and are killing one another in collisions. People don't cycle more because they're scared of being hit by a car. At least 100 cyclists die from being hit by cars each year in the UK and over 2,000 are seriously injured. The research proposed here aims to make it less likely that cyclists have such accidents, which will encourage more people to cycle. Collisions between cars and bicycles tend to happen at road junctions. However, collisions also happen when cars overtake and when this happens it is serious, because being hit by an overtaking car is one of the worst things that can happen to a cyclist. If we understood what determines how close drivers get to the cyclists as they overtake, we could do something to make collisions less likely, either in the way we construct our roads or, more likely, with advice to cyclists about how they should ride. There are currently three big ideas about what determines drivers' overtaking closeness, and we plan to test them all. The first idea is that the distance a driver leaves when overtaking a cyclist is related to the distance the cyclist left between themselves and the edge of the road. In other words, many cyclists are convinced that if they ride away from the edge of the road, drivers will leave more space as they overtake, making the cyclist safer. We know that a lot of cyclists rely on this idea for their safety, but it has never been properly tested and all we have are lots of unscientific reports based on people's experiences. The idea urgently needs testing properly.We plan to do this by fitting a bicycle with a distance sensor feeding into a computer. This will record how far away each vehicle is as it passes the bicycle. The computer will also get information from a video camera (so we can later see what the overtaking vehicles were) and a microphone, so the cyclist can record any other useful information about what is happening as people overtake. By riding the bicycle along a series of roads we can directly test the idea that the distance to the bicycle's left affects the space drivers leave as they overtake. We can also see whether the really important thing is not the space to the cyclist's left but perhaps how wide the road or the lane is. This instrumented bicycle also allows us to test the other two ideas we are interested in. The first of these is that some vehicles-particularly buses-will overtake cyclists in a more risky way than others. We suspect this because we recently did a survey of almost 5,000 cyclists and asked them about any accidents they had had. We found that accidents involving buses stood out from other collisions, as they almost all happened as the bus overtook. We are therefore very keen to see whether bus overtaking is notably different in this study.The final thing we wish to do is to have the rider wear a cycle helmet for half the time and no helmet for half the time. A lot of experienced riders report that drivers are more careless around a cyclist if the cyclist is wearing a helmet. If this is true, it would suggest that wearing a helmet might actually have the opposite effect to that intended, and put the wearer in greater danger. It will therefore be of great interest to see whether drivers tend to overtake closer when the cyclist is helmeted than when he has no helmet. The findings from this study will be widely distributed to interested parties. The results, whatever they prove to be, will be very valuable for guiding road safety activity. We will therefore inform local and national government and other road safety groups (e.g., BRAKE, RoSPA) and groups interested in cyclist safety (CTC, LCC, etc.).