How to Avoid Rear-End Collisions

This article is part of a series to help drivers practice for and pass the California DMV written permit test. Most, if not all, of the driving issues discussed in this series also apply to the rules of the road throughout the US.

The most common kind of car crash is a rear-end collision. Here are two simple ways you, as a driver, can avoid rear-end collisions.

I teach driver education in Portland, Oregon. In the past couple weeks, either driving to meet my students or driving with my students, I’ve come across four crashes. I say crash for a reason. One of the things we teach our students is to avoid using the word “accident.” “Accident” implies that the event was out of participants’ control, that it just happened. If it’s just an accident, no one is to blame.

“Crash”—or “collision”—are neutral terms. They don’t implicitly make a claim about blame, or a lack of it. When describing a situation where vehicles collide, run off the road, or hit other objects, we train students to call such events “crashes.” It’s up to the police and the insurance companies to rule on who’s to blame for a crash and who isn’t, not us.

One kind of crash for which it’s relatively easy to assign blame are the kinds of crashes I’ve seen in the past couple weeks. They all fit a pattern. One car collided with the rear end of another. More often than not, who’s to blame for a rear-end crash? The answer is almost invariably the person driving the vehicle that crashes its front end into the rear end of the other vehicle. Why is this the case? Because, by law, vehicles are obligated to yield the right-of-way to vehicles in front of them. If you’re following another vehicle, it’s your responsibility to make sure you don’t hit the vehicle in front of you.

Stay alert

How do you make sure this happens? First off, you have to stay alert. One of the crashes I witnessed was an all too common scenario. I was driving on the freeway, I-84, that begins in downtown Portland and splits the eastern side of Portland in half. It’s a busy freeway that frequently has bumper-to-bumper traffic, especially during rush hour. At this time, about 12:30 in the afternoon on a Saturday, traffic was moderate, but moving. At curves, traffic slowed. It was the typical surge traffic pattern you see when there’s flow, but enough vehicles are on the road that the flow isn’t steady, and frequently well below the posted speed limit.

In a middle lane, a pickup truck had rear-ended a sedan. In all likelihood, two conditions conspired to cause the crash. First, the driver of the pickup truck wasn’t fully alert. As you know, drivers of vehicles ahead of you will give clues about their behavior. First and foremost, their brake lights go on when they slow down. If they’re slowing down slightly, the brake lights may on and off once or twice, because they’re tapping the brake pedal. If they’re slowing down quickly, the brake lights go on and stay on.

Maintain a safe following distance

So perhaps the driver of the pickup truck didn’t notice the sedan’s brake lights. Alone, this may have not been enough to cause a crash. The second condition that made the pickup truck driver’s lack of alertness all the more dangerous was that, in all likelihood, he wasn’t maintaining a safe following distance.

In Oregon, the law is that you must maintain a 2 to 5 second following distance. In driver ed, we teach at least 4 seconds to how to avoid rear-end collisions. This means that it takes you 4 seconds to reach a landmark that the vehicle in front of you just passed. Why 4 seconds and not 2? Because in many circumstances, 2 seconds just isn’t enough time to react to sudden events in front of your vehicle. With 4 seconds, you have time to perceive, interpret, and respond to events in front of you, all without breaking a sweat.

During burst traffic on the freeway, when you’re repetitively slowing, stopping, inching forward, and accelerating to speed, it’s all too easy to get lulled into a state of distraction. The surges in the flow of traffic, the rhythm of the brake lights ahead of you, become almost hypnotic. These are times when it’s important to stay alert–and maintain that 4 second following distance.

After a crash, pull over to the shoulder of the road

On a side note, incredibly, after the crash on the freeway, which was minor—only a cracked fender—the two drivers parked their vehicles in the middle lane where the crash occurred. They got out of their vehicles and stood in the road inspecting the damage and talking. In the middle of a busy freeway! Meanwhile, stopped vehicles piled up behind them in a column, as other vehicles whizzed by in the adjacent lanes.

When no one is hurt in a crash and the vehicles remain functional, the thing to do is pull over to the shoulder of the road. When safely to the side of the road, that’s the time to inspect damage, exchange info, and, if you need to, call for help. By standing in the middle of a busy freeway, those two drivers could very well have turned a minor fender-bender into a major tragedy.