SAN DIEGO, Calif. — Drivers should be at least three to four seconds behind the vehicle they’re following to mitigate the risk of rear-end collisions, according to a new study by DriveCam Inc., a global Driver Risk Management company.

Analysts at the firm’s Risk InfoCenter recently reviewed incidences of rear end crashes to determine the impact of following distance on likelihood of collision.

"There is no greater risk of being struck from the rear when the subject vehicle is maintaining less than two seconds than having greater than two seconds following distance," explained Del Lisk, DriveCam vice president, safety services.

However, the story is different when it comes to the subject vehicle rear ending the vehicle ahead, the study found. "Incidents involving the subject rear ending the lead vehicle where the subject vehicle had less than two seconds of following distance was almost three times as common as those where the driver was maintaining a distance of two seconds or greater."

Rear end crashes are the second most common claim for most fleet operators. They make up 17 percent of all claims and cost over $13,000 per claim. Although recommended following distances can vary by weight and size of vehicle, most nationally recognized driver training programs advocate a minimum following distance of three or four seconds.

A large number of rear end crashes involve a change in speed
by the lead vehicle or an interruption to the flow of traffic: Study

The study also showed that a large number of rear end crashes involve a change in speed by the lead vehicle or an interruption to the flow of traffic in the lane.

In fact, more rear end crashes happen in the farthest right lane than other lanes when on city streets. The right lane has pedestrians, parked cars and turning vehicles that are constantly disturbing traffic flow. Following this same logic, the left most lane was next most frequent since this lane can be impacted by traffic slowing or stopping to make a left turn. The center lane had far fewer incidents of rear end crashes.

“This is partially due to the fact that more of the roads had only one or two lanes of same direction traffic,” explained Lisk. “However, it may also be due to the fact that the center lane has fewer traffic flow disturbances.”

Based on the findings, the company offers a few tips for avoiding rear-end incidents:

When possible, avoid the far right and left lanes, except when preparing to turn; drive in the center lane as much as possible (except where prohibited by state and local laws); maintain the proper following distance appropriate for the weight and size of the vehicle being driven; and try to maintain a steady speed to reduce sudden stops and starts; this will also assist with fuel efficiency, notes DriveCam.