What is the 3-Second Rule?

The National Safety Council recommends the 3-Second Rule to determine a minimum safe following distance at all speeds.

The 3-SECOND rule:  When the driver in front of you passes a stationary object on the roadside, begin counting… “One-Thousand-One, One-Thousand-Two, One-Thousand-Three”; then, you should pass that same object. 

Add another second for adverse weather and road conditions. 

Why use the 3-Second Rule?  

Over 60 years ago the National Safety Council recognized the need for defining the safe following distance. They recommended that drivers allow one car-length for each 10 mph.

In the 1970’s they replaced the car-lengths with the “2 second rule” because it was easier to apply at various speeds. In the 1990’s, they increased the time to 3 seconds. Now, they are considering 4 seconds to allow for distractions.

State Drivers’ Manuals – over half the 50 states recommend 3 seconds or more (up to 6 sec) in their Drivers’ Manuals. Most all the other states recommend 2 seconds with additional time for adverse weather or road conditions.

30% of all crashes are rear-end collisions (NHTSA 2020 stats). 

                            Following too close is a major cause of crashes and road-rage. 

                                                                    Help make our highways safer and friendlier.