Dangers of following too closely

- Published Aug. 24, 2010

A common driver error fleet instructors see, is following or stopping too close to another vehicle.

Ask yourself, how far back should you stop behind another vehicle in traffic, or follow behind another vehicle in traffic? If you’re already scratching your head, read on.

Three-second rule

The most accurate way to measure space while driving behind another vehicle, is by following what is commonly known as the three-second rule. This means keeping a minimum three-second space between you and the vehicle you are following.

To figure out the three-second following distance, look at the vehicle in front of you.

When the back of that vehicle passes a fixed object like a sign, a tree or a road marking, start counting. Count one-thousand-and-one, one-thousand-and-two, one-thousand-and-three.

If you realize you're too close

If the front of your vehicle reaches the object before you are finished counting, you are following too close:

• Slow your vehicle down and count once more.
• If someone cuts in front of you, you will need to set up your three-second following distance again.
• The three-second rule will need to be increased when driving in bad weather or at highway speeds.

The only exception to this rule involves drivers of large commercial vehicles who should use a minimum four-second following distance in traffic.

Allowing space when you stop

When stopping in traffic, always have an out. Leave approximately one vehicle space between you and the vehicle stopped in front of you. Doing so can protect you from getting stuck in traffic or possibly in a crash with another vehicle.

Use extra caution when coming to a stop behind a large vehicle on an incline. Large vehicles can roll back as much as 4.5 metres when the driver's foot is taken off the brake pedal to accelerate.

Remember, as a driver you have the most control over the space in front of your vehicle, always leave yourself an out.