Hu Wen, McCartt Anne T
a Insurance Institute for Highway Safety , Arlington , Virginia.
Traffic Inj Prev. 2016 Sep;17 Suppl 1:53-8. doi: 10.1080/15389588.2016.1189076.
In May 2007, Montgomery County, Maryland, implemented an automated speed enforcement program, with cameras allowed on residential streets with speed limits of 35 mph or lower and in school zones. In 2009, the state speed camera law increased the enforcement threshold from 11 to 12 mph over the speed limit and restricted school zone enforcement hours. In 2012, the county began using a corridor approach, in which cameras were periodically moved along the length of a roadway segment. The long-term effects of the speed camera program on travel speeds, public attitudes, and crashes were evaluated.
Changes in travel speeds at camera sites from 6 months before the program began to 7½ years after were compared with changes in speeds at control sites in the nearby Virginia counties of Fairfax and Arlington. A telephone survey of Montgomery County drivers was conducted in Fall 2014 to examine attitudes and experiences related to automated speed enforcement. Using data on crashes during 2004-2013, logistic regression models examined the program's effects on the likelihood that a crash involved an incapacitating or fatal injury on camera-eligible roads and on potential spillover roads in Montgomery County, using crashes in Fairfax County on similar roads as controls.
About 7½ years after the program began, speed cameras were associated with a 10% reduction in mean speeds and a 62% reduction in the likelihood that a vehicle was traveling more than 10 mph above the speed limit at camera sites. When interviewed in Fall 2014, 95% of drivers were aware of the camera program, 62% favored it, and most had received a camera ticket or knew someone else who had. The overall effect of the camera program in its modified form, including both the law change and the corridor approach, was a 39% reduction in the likelihood that a crash resulted in an incapacitating or fatal injury. Speed cameras alone were associated with a 19% reduction in the likelihood that a crash resulted in an incapacitating or fatal injury, the law change was associated with a nonsignificant 8% increase, and the corridor approach provided an additional 30% reduction over and above the cameras.
This study adds to the evidence that speed cameras can reduce speeding, which can lead to reductions in speeding-related crashes and crashes involving serious injuries or fatalities.
2007年5月,马里兰州蒙哥马利县实施了一项自动测速执法计划,允许在限速35英里/小时及以下的住宅街道和学校区域安装摄像头。2009年,该州的测速摄像头法律将执法阈值从超过限速11英里/小时提高到12英里/小时,并限制了学校区域的执法时间。2012年,该县开始采用走廊式方法,即摄像头沿道路路段的长度定期移动。评估了测速摄像头计划对行驶速度、公众态度和撞车事故的长期影响。
将该计划开始前6个月至开始后7.5年期间摄像头安装地点的行驶速度变化,与附近弗吉尼亚州费尔法克斯县和阿灵顿县对照地点的速度变化进行比较。2014年秋季对蒙哥马利县的司机进行了电话调查,以了解与自动测速执法相关的态度和经历。利用2004 - 2013年期间的撞车事故数据,逻辑回归模型研究了该计划对蒙哥马利县符合安装摄像头条件道路以及潜在溢出道路上撞车事故导致 incapacitating 或致命伤害可能性的影响,以费尔法克斯县类似道路上的撞车事故作为对照。
该计划开始约7.5年后,测速摄像头使平均速度降低了10%,车辆在摄像头安装地点超过限速10英里/小时行驶的可能性降低了62%。2014年秋季接受采访时,95%的司机知晓摄像头计划,62%的司机表示支持,且大多数人收到过摄像头罚单或认识收到过罚单的人。包括法律变更和走廊式方法在内的改进后的摄像头计划的总体效果是,撞车事故导致 incapacitating 或致命伤害的可能性降低了39%。仅测速摄像头就使撞车事故导致 incapacitating 或致命伤害的可能性降低了19%,法律变更导致的降低幅度不显著,为8%,走廊式方法在摄像头的基础上又额外降低了30%。
本研究进一步证明,测速摄像头可以减少超速行为,进而减少与超速相关的撞车事故以及涉及重伤或死亡的撞车事故。