Keep a safe following distance before overtaking

Do not approach too closely while waiting to overtake. Maintain enough room to see ahead, react to unexpected braking and stop safely if a hazard develops. Increase the gap when the behaviour of the driver ahead is uncertain or difficult to assess. The margin must be at least as great as the distance travelled during reaction time and must also allow for braking in the actual conditions. It is therefore not always numerically equal to braking distance alone.