Ford Motor Company

One of the first things we’re taught when we learn to drive is to check our mirrors constantly. We’re supposed to check our rearview and side mirrors before doing almost anything; turning or changing lanes also calls for a quick glance over the shoulder. Unfortunately, traffic conditions can change in a split second — a path that was clear when you checked might not be clear now — and even then, you might have overlooked a car hanging out alongside you, right in your blind spot where your mirrors simply can’t reach. Blind spots, and the cars that occupy them, have probably been a hazard of the road for almost as long as there have been cars, and even though mirrors are great, they alone can’t eliminate blind spots. (And of course, the bigger your vehicle is, the bigger your blind spot is, too, and the greater the hazard.) Since about 300 people die in the United States every year due to blind spot-related vehicle accidents, more automakers are beginning to incorporate blind spot monitor technology into their cars.

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The Solution

If you’ve ever driven a car with modern active safety features such as adaptive cruise control, front collision warning and mitigation, emergency brake assist, lane keep assist, or park assist, you might have noticed that the vehicle had sensors, or even cameras, embedded around it. These sensors use radar or sonar to constantly monitor the car’s surroundings and help the driver maintain a cushion of safety. Just like adaptive cruise control and front collision warning can tell you if you’re getting too close to the car in front of you, a blind spot monitor can tell you if there’s a car next to you that you might not be able to see, and alert you to its presence before you attempt to change lanes. The way blind spot monitor systems interact with the driver varies slightly from car to car. For instance, some vehicles provide the warning indicator whenever the blind spot monitor is triggered, while others only alert the driver after he or she signals a turn. Regardless of these differences, they all do the same job — reducing collisions on the road.

[Read: What is Adaptive Cruise Control?]

Getting a Car With a Blind Spot Monitor

Volvo Cars of North America

Buying a car (whether new or used) with a blind spot monitoring system should be fairly straightforward, since it’s becoming an accessible and affordable option even on mid- and low-end cars. (It’s common for new technology to be introduced on high-end cars — in this case, certain 2005 model-year Volvos — and trickle down to less expensive models as the technology gets older and more affordable.) When you’re shopping for a car with a blind spot monitor, you should be aware that some manufacturers come up with other names for the technology (“lane change assist” is a common one). Blind spot monitors are often bundled into options packages with other safety features that use the same kind of technology, so be sure to research the available features on cars you like before you go to the dealership, and try out the blind spot monitor on your next new car test drive.

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