Stop, go, Floor it: The Dilemma Zone

By Mark

Welcome to the Dilemma Zone.

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It sounds like a reality TV show, but it's actually something most drivers encounter every day: the moment when, approaching a yellow traffic light, you must decide to continue through the intersection at the same speed, hit the gas or apply the brakes.

Each of these decisions carries risks. A sudden stop could result in a rear-end collision. A burst of acceleration could bring a ticket. Easing through the intersection makes you a T-bone target.

Research indicates that only 1.4% of drivers cross the line once the light turns red -- but 20% of fatalities happen at intersections, according to the Federal Highway Administration.

While most of us safely navigate intersections every day, it only takes one bad decision to put your car, life and insurance rates at risk.

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So what is the Dilemma Zone?

Hesham Rakha, director of the Center for Sustainable Mobility at the Virginia Tech Transportation Institute, defines the Dilemma Zone as the place where a driver has no feasible choice. He can neither stop nor continue through the intersection before the light changes to red.

The standard yellow time is 4.2 seconds on a 45 mph road. On faster roads, the length is longer. The formula is based on two assumptions: It takes the average driver one second to perceive and react to a yellow light and 3.2 seconds to safely stop the car.

However, research released last fall found that 4.2 seconds is just not enough time in many situations.

Rakha and fellow researchers determined that perceiving and reacting to a light change takes a bit longer than one second and deceleration times are much longer than standard yellow light times. Poor road conditions slow both reaction and stop times.

Data showed that 43% of drivers who crossed the stop line during a yellow light were unable to clear the intersection.

A warning light for the caution light

A longer yellow light isn't necessarily the answer, Rakha says.

"You could design the yellow time so that 90% of drivers - or 95% -- are not caught in the dilemma zone. But the higher you go, the longer the yellow time is, which increases the time cross traffic is stopped," he says.

That would not only increase pollution, Rakha notes, but also the risk of more drivers taking chances to avoid a long light.

Other solutions the group suggests could include warning lights that make drivers aware that a green light is about to change, or an in-dash display that communicates with the traffic lights and makes the decision for the driver.

Until the day those smarter yellow lights appear, drivers must make their own choices. The safest one is almost always to stop.

What is the law?

Laws regarding yellow lights vary by state, but in general there are two schools of thought.

Many states use a "touchdown" rule. This means if the car breaks the plane of the white line at the intersection before the light turns red, the driver is allowed to clear the intersection.

Other state laws are more vague. The wording goes something like this: Traffic facing a yellow signal shall stop before entering the intersection unless so close that a stop may not be safely made. These laws are bit harder to enforce.

A Wisconsin police officer on an forum discusses enforcement issues. "The yellow light violation can be enforced, but it has to be pretty blatant. I've written and successfully argued it in court, but I had video showing the vehicle was clearly able to stop, but sped up to make the light."

In 24 states and the District of Columbia, red light cameras take enforcement to the next level, penalizing any driver who crosses the white line while the light is red, even by only a foot or two.

A study by the Insurance Institute for Highway Safety (IIHS) looked at 14 cities using red light cameras and found that the combined per capita rate of fatal red light accidents decreased by 35%. On the flip side, The Federal Highway Administration and Virginia Transportation Research Council found that red light cameras probably caused more rear-end crashes.

What's worse for my insurance?

"If you stop for a yellow light, you are blameless," consumer analyst Penny Gusner says. "Even if you get hit from behind, it's their fault, not yours."

Zipping through the light to avoid a tailgater is no excuse, unless an officer happens to cut you some slack. A camera won't know the difference.

Any accident after you've run a red light is almost always your fault, Gusner says. (Read about comparative negligence laws.)

While fines for a red light violation can vary dramatically, it's the black marks on your motor vehicle record that eventually cost you the most. Your insurance company can calculate rates based only on what it finds there. (See's "Uh-Oh Meter" to see how different infractions typically affect your premiums.)

A single red-light ticket might be forgiven, cost you a good driver discount, or actually raise your rates, Gusner says, depending on your insurer's surcharge schedule. "You can ask them about it even before you get a ticket," she says. "It can make a difference down the road."

Many jurisdictions don't put red-light camera violations on motor vehicle records at all.

Staying safe

So how do you stay safe when approaching an intersection and the light is yellow?

Maria A. Wojtczak, owner of Driving MBA, offers this advice: "Use the broken white or yellow lines as indicators. Each line represents 10 mph. If you only have two lines before entering the intersection and are going 40 mph, you have reached the point of no return and must continue through the light. If there are four or five lines before the intersection you have plenty of time to make a safe stop."

Experts also remind drivers to avoid changing lanes in an intersection -- which is also illegal.

The original article can be found at, go, floor it: The Dilemma Zone