Following Distance

Most all rear end collisions can be prevented by maintaining a safe following distance from the vehicle in front of you.

Stopping distance is a combination of reaction distance and braking distance. Reaction distance is the distance that your vehicle travels from the time you see a reason to apply brakes to when you actually move your foot to the brake pedal and begin to slow down. If you are too close to the vehicle in front, you will hit them NO MATTER HOW GOOD A DRIVER YOU ARE. You can only get to the brake as fast as a human can move and by the time you get there, if the guy in front is already breaking hard, you don't have a chance.

What distance should be maintained?

The three-second rule is a rule of thumb to maintain a safe following distance. To estimate the time, a driver can wait until the rear end of the vehicle in front passes any fixed point on the roadway (road sign, mailbox, line/crack/patch in the road). After the car ahead passes a given fixed point, the front of one's car should pass the same point no less than 3 seconds later. If the elapsed time is less than this, one should increase the distance, then repeat the method again until the time is at least 3 seconds. The 3 second rule is for ideal conditions. So increase the distance in conditions like slick roads, fog, heavy rain, sun glare, dark or unfamiliar areas, and heavy traffic.

How much distance should you leave when you stop behind another vehicle?

Stop far enough behind the vehicle in front so that you can see their back tires touching the road. It gives you advantages such as …

• If you are hit from behind by another vehicle there is less chance you will hit the vehicle in front of you.
• You can see much more of the road ahead, signs and traffic light (especially if it’s a large truck you are behind).
• There’s less likelihood of the vehicle in front rolling back into your vehicle if you’ve stopped facing uphill.
• If the vehicle ahead of you breaks down or stalls you can more easily get around them.
• Allows you space to steer and drive away if you need to get out of your current traffic lane.