The two-second rule is a rule of thumb by which a driver may maintain a safe trailing distance at any speed.[1][2] The rule is that a driver should ideally stay at least two seconds behind any vehicle that is directly in front of his or her vehicle. It is intended for automobiles, although its general principle applies to other types of vehicles. Some areas recommend a three-second rule instead of a two-second rule to give an additional buffer.
The rule is not a guide to safe stopping distance, it is more a guide to reaction times. The two-second rule tells a defensive driver the minimum distance needed to reduce the risk of collision under ideal driving conditions. The allotted two-seconds is a safety buffer, to allow the following driver time to respond. The practice has been shown to considerably reduce the risk of collision and also the severity of any injuries if a collision occurs. It also helps to avoid tailgating and road rage for all drivers.
A large risk of tailgating is the collision avoidance time being much less than the driver reaction time. Driving instructors advocate that drivers always use the "two-second rule" regardless of speed or the type of road. During adverse weather, downhill slopes, or hazardous conditions such as black ice, it is important to maintain an even greater distance.
- ^ "The two-second rule". Road Safety Authority (Government of Ireland). Archived from the original on March 9, 2012. Retrieved December 13, 2011.
- ^ "NYS DMV - Driver's Manual - Chapter 8: Defensive Driving". New York State Department of Motor Vehicles. September 2011. Retrieved December 13, 2011.