In the time it takes to read this sentence, you could save a life—maybe even your own. Read on.
Accidents can occur when your vehicle-following distance is too close (known as tailgating). NASCAR drivers tailgate to gain speed advantage by drafting off other vehicles. They also get in a lot of accidents. From a list of 42 NASCAR drivers from 2011-2015, accidents happened from 0.25 to 1.90 per 500 miles driven, with a mean score of one every 650 miles. In fact, most races include multiple accidents. Fortunately, their cars are packaged and fireproofed to a great extent, with fire trucks and paramedics standing by.
The driving public travels about 1,100 times farther between accidents than NASCAR drivers, but still typically within two seconds or less following distance. The difference in rates has much to do with perception and reaction times. When a lead vehicle sees a hazard, such as an animal running into the road, there is about one second of perception time for our brain to recognize the hazard. From the time your brain recognizes the hazard, the reaction time for the foot to touch the brake pedal, is another 0.75 second.
When following other vehicles at two seconds, these reaction times leave only a 0.25-second distance to avoid a rear-end collision. Vehicles can usually stop with a two-second following distance if the drivers are paying attention and not distracted. Large trucks with loads many times higher than small vehicles, require much greater distances to stop, even with sophisticated, heavy-duty braking systems.
To avoid rear-end tailgating accidents, increase your following distance to three or more seconds for small vehicles, and six or more for trucks. (One trucking company requires an eight-second distance for their double-trailer loads.) Such safe following distance practices will add a few more seconds to your trip, but may save lives. Take five, stay alive.