Following distance: how the 2-second rule works

You keep two car lengths from the car in front. That feels like plenty. But on the motorway, that's almost nothing. At a hundred kilometres an hour, you cover twenty-eight metres a second. Two car lengths is about ten metres. You cross that in a third of a second.

And your reaction time? The CBR works with one second: see the brake lights, foot on the brake. A third of a second of room, a full second to react. The room runs out before you do. So don't count cars. Count seconds. In good weather, keep at least two seconds.

That's an actual CBR exam question. Here's how: pick a post or a sign by the road. When the car in front passes it, count: twenty-one, twenty-two. Reach it sooner? Then you're too close. Ease off. In rain or fog, keep more than two seconds. Send this to the tailgater in your family.

Don't count cars. Count seconds.