Do car GPS devices cause accidents?

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Maybe you've heard the stories. Accounts are stacking up of drivers performing illegal and dangerous actions only to blame the inevitable accident on their car GPS unit. The rural village of Wedmore, England, for example, has seen its share of truck drivers wedged between buildings because they blindly followed the route their GPS system planned out -- regardless of the fact that trucks are prohibited from the village because of their size. And in the United States, a man steered his car onto railroad tracks at the command of his GPS device to "turn right, now." Luckily, he was able to escape before an oncoming train slammed into his car.

GPS navigation systems are no longer strictly luxury accessories. Approximately 7 percent of 220 million cars in the United States have some type of GPS navigation system (factory installed or aftermarket, portable or built-in) and 13 percent of the 200 million cars on the roads in Europe use GPS devices [source: Automotive Business Review]. GPS has hit the mainstream.


­GPS, which stands for Global Positioning System, is made up of a group of satellites. These satellites communicate with your GPS navigation device to pinpoint your location, give or take 164 to 328 feet (50 to 100 meters) [source: Corvallis Microtechnology, Inc.]. Your position is then overlaid with digital mapping and navigation information stored within your GPS receiver. Once your device knows your location, it's able to plan driving directions for you, suggest a route around traffic congestion, find a nearby gas station, hotel or the local Starbucks. What it won't do is drive your car for you. As GPS devices go mainstream, there are a growing number of accounts about the devices routing users into lakes, onto train tracks or the wrong way down a one-way street. GPS devices have caused an estimated 300,000 car accidents in the United Kingdom [source: Carey].

Let's look more closely at the reasons why drivers with GPS devices are at an increased risk for accidents, whether it's because they're relying more on what their GPS device tells them and less on maps, or because they're ignoring common sense or their own eyes.


GPS Dangers and Accidents


­Remember that parental standby, "If your friends jumped off a cliff, would you?" As it turns out, this is good advice to heed when you use a GPS device: If your GPS tells you to drive off a cliff, would you?

Since GPS navigation systems are now common, a contributing link between the devices and accidents has been identified. While the reasons are varied, it often boils down to humans being human.


One of the most common human errors when it comes to using a GPS device is overconfidence in how smart that navigation system is or isn't. Why plan when your GPS will tell you where to go? Well, GPS devices are fallible; they're made so by satellite communication errors and outdated or inaccurate maps. Even when maps are current, some mapping and navigation information doesn't take into account road types. With this type of software error, the road that may look like the shortest distance between Point A and Point B might actually be an unpaved private drive. If your GPS device doesn't recognize it as such, it could add the road to your route.

Because of these factors, drivers find themselves driving on unsafe terrain and into other hazards, such as artificial lakes or train tracks. The more confident you are in what your GPS device tells you, the less likely you are to notice something's wrong. Accident risk increases when drivers take their GPS device's instructions too literally: Warnings of "when possible, make a legal U-turn" send some veering into oncoming traffic.

Driver inattention and distraction also increase accident risk. Many of us have seen such drivers on the road: those who are having their morning cup of coffee, talking on the phone and reading the paper all while behind the wheel of their car. Sure, it's hard to eliminate all distractions while driving -- who isn't guilty of tuning to a better song? In a study conducted by the Network of Employers for Traffic Safety (NETS), spilling hot coffee on yourself and dropping something on the floor are the two most common driver distractions. But the National Highway Traffic Safety Administration estimates that driver distraction plays a role in 25 to 30 percent of the roughly 1.2 million car crashes in the United States each year [source: Stutts]. The greater number of devices in your car, from cell phones to GPS navigators to onboard entertainment systems, the greater the distraction possibilities. NETS also found that when GPS users mute the device they increase their distraction level -- without the voice commands, drivers spent more time looking at the screen than the road [source: Smart Motorist].

It's no doubt that in most cases GPS navigation systems can get you to your destination unharmed, especially if you do a little groundwork before hitting the road. Prep the device before taking off to avoid the distraction of adjusting it while driving -- that includes not only setting your start and end destinations but also adjusting settings. And minimize distraction by pulling over or relying on a passenger to make changes during the trip.

Consult a map and pay attention to the surroundings and road signs -- GPS may be convenient but it can't replace common sense. If things don't look right, they probably aren't.


Lots More Information

Related HowStuffWorks Articles

  • Carey, Tanith. "SatNav danger revealed: Navigation device blamed for causing 300,000 crashes." The Mirror. 2008. blamed-for-causing-300-000-crashes-89520-20656554/
  • "Distracted Drivers Cause Motor Vehicle Accidents."
  • Helperin, Joanne. "The Fastest Way From Here to There - GPS Navigation Systems." 2007.
  • "Introduction to the Global Positioning System for GIS and TRAVERSE." Corvallis Microtechnology, Inc. 2000.
  • Johnson, Chris. "The Role of Trust and Interaction in GPS Related Accidents:A Human Factors Safety Assessment of the Global Positioning System (GPS)." Department of Computing Science, University of Glasgow.
  • Lyall, Sarah. "Turn Back. Exit Village. Truck Shortcut Hitting Barrier." The New York Times. 2007.
  • Sayer, Peter. "Study: Navigation Systems Could Cause Accidents." PCWorld. 2008.
  • "Statement of L. Robert Shelton, Executive Director, National Highway Traffic Safety Administration Before the Subcommittee on Transportation and Infrastructure - U.S. House of Representatives." National Highway Traffic Safety Administration. 2001.
  • Stutts, Jane C., Donald W. Reinfurt, Loren Staplin, Eric A. Rodgman. "The Role of Driver Distraction in Traffic Crashes." Highway Safety Research Center. University of North Carolina. 2001.
  • "TomTom steers through another successful quarter." Automotive Business Review. 2008.
  • "Train Hits Car, and a G.P.S. Is Blamed." The New York Times. 2008.