NIHERST: Tsunamis

As noted in the section on Driver Reaction Time, a slight increase in the driver’s reaction time can have a profound effect on the risk of a crash especially at high speeds. It is estimated by the National Highway Traffic Safety Administrations in the United States that one in four reported accidents involve some kind of driver distraction. Different age groups tend to have different things which distract them when driving. Drivers younger than 20 tend to be distracted by the changing of a CD or radio station in the car. Drivers between 21 and 29 tend to be distracted by people or passengers in the car such as young children. Drivers 65 and older tend to be distracted by objects and events outside the car.

A 2003 study conducted to determine the prevalence of diver distractions found that all of the drivers in the study were distracted at some point, 90 percent by something outside the car and 100 percent by something inside the vehicle. Every driver in the study manipulated vehicle controls and nearly all reached for objects in the vehicle. Most adjusted the sound system or were distracted by objects or events outside the vehicle. About one-third of those studied used a cell phone while driving, and 40 percent engaged in reading or writing. This study found that drivers performed some potentially distracting activity up to 16 percent of the total time their vehicles were moving.

Many studies by North American road safety researchers have found that mobile phones are one of many potentially dangerous driver distractions. Studies have found that when the brain has to process too many tasks at the same time activities which are more core take precedence over more recently developed skills so that speaking and listening (which are learned at a young age) are likely to squeeze out a more recently learned process such as driving. According to a study by the Human Factors and Ergonomics Society, cell phone distraction causes 2,600 deaths and 330,000 injuries in the United States every year.

Drivers talking on cell phones were 18 percent slower to react to brake lights although they did keep a 12 percent greater following distance behind another vehicle. The drivers using mobile phones also took 17 percent longer to regain the speed they lost when they braked, frustrating other motorists. The net result of cell phone use by drivers was that they impeded the overall flow of traffic. Previous research showed that even hands-free cell phone use distracted drivers. The reason is that drivers are so distracted by the conversation that they look but do not see. Both young and old adults made more errors in detecting important changes and took longer to react to the changes. Impaired reactions took seconds, not just fractions of seconds, so stopping distances increased by car lengths. Scientists also found that motorists on cell phones are less adept than drunken drivers with blood alcohol concentrations greater than 0.08. Interruptions to driving, such as answering a cell phone call, are likely to be more dangerous if they occur during maneuvers like merging (changing lanes) in traffic to exit a highway.

Other distractions that could prove to be just as dangerous, or even more so, as cell phone use while driving, include wireless Internet access and e-mail, DVD players or televisions mounted on dashboards or within view of the driver, GPS navigation systems, and voice recognition systems.

Road Safety: Driving Distractions