What is the safe distance between 2 cars?

Saturday, 14 July, 2007 by121motor

An important aspect of driving is to be able to maintain a safe distance with other cars. The ability to stop a car safely depends on how you maintain a distance with another car. It is also depends on the speed. On average, it takes the driver approximately 0.75 second to respond before stepping on the brake pedal. The moment the brake pedal is depressed, it takes another 2 seconds for the car to a complete and safe stop. Therefore, the time added for the driver to react and then to step on the brake pedal is just about 3 seconds. Thus, we have the 3 seconds rule.

The practice of the 3 seconds rule helps to avoid tailgating. A driver that deliberately follows another car too closely is called “tailgating”. Tailgating is recognized as a driving behavior that is easily and often mistaken for road rage. If you notice someone is tailgating you, move your car to another lane or simply turn off the road and let the tailgating car to pass. One of the reasons for rear end collisions are mostly due to tailgating.

At daytime when the weather is good with dry roads and less traffic volume, it will be safe to follow the 3 second rule to ensure a safe distance from the car ahead. The distance changes at different speed.

• Select a stationary object on the road ahead, such as an overpass, tree, lamp pose or sign to determine the right following distance.

• Note the car ahead passes the object and gradually count “one thousand, two one thousand, three one thousand” (this would be exactly 3 seconds). Ascertain there are 3 seconds between your car and the car ahead to allow sufficient time and distance to response and avoid to any possible danger on the lane ahead of you. You are following too closely if you reach the selected object before completing the count.

However, it would be safer to practice the 6 seconds rule for added safety at times of inclement weather, night driving, heavy traffic or anytime when weather conditions are not ideal (smoke, fog).

THE 3 SECONDS RULE		Safe Interval Should Be >>	3 SECONDS	6 SECONDS
SPEED	DISTANCE TRAVELED	For These Conditions >>	GOOD	MARGINAL
50 km/h	14 meter per second		42 meter	84 meter
70 km/h	19.5 meter per second		58.5 meter	117 meter
90 km/h	25 meter per second		75 meter	150 meter
110 km/h	30.5 meter per second		91.5 meter	183 meter
130 km/h	36 meter per second		108 meter	216 meter

The following distance must be at least sufficient to provide the opportunity to react and prevent a potential hazard. If you are following a car ahead that is driving at 100 km/h, you will require about 1½ seconds on average to react if this car brakes out of a sudden. You will most likely run into the car ahead if you do not maintain this distance.

Most of us require more than 2 seconds reacting to any potential danger ahead. There will be high chances of running into the car ahead if you fail to brake with the same intensity as the vehicle in front of you. In any circumstances, there is no guarantee that a vehicle ahead will break on time to avoid the danger. Therefore, it is highly recommended to follow the 3 seconds rule to keep the right distance between you and the car in front of you.