Study says lane departure warning systems don’t prevent crashes

2012-Mercedes-Benz-CLS-63-AMG-Drivers-Side-MirrorCar companies are constantly developing new technologies to keep drivers safer, but how effective are these new gizmos? The Highway Loss Data Institute, an affiliate of the Insurance Institute for Highway Safety, determined that not all safety systems work as advertised. A study by the institute found that lane departure warning (LDW) systems can make driving more unsafe.

“Lane departure warning appears to hurt, rather than help, though it’s not clear why,” the study said. LDW systems use sensors to see when a car strays out of its lane, and alert drivers to take corrective action. The study found that cars equipped with LDW have a 10 percent higher crash rate than cars without it.

The Insurance Institute did not reach any solid conclusions about that figure, but IIHS chief research officer thinks it could be down to human error. Drivers may become annoyed by the systems’ warnings and shut them off, or ignore them.

The newness of LDW may also encourage people to use it as a crutch. Some drivers may assume that their LDW system will alert them in time to prevent a crash in every situation, and consequently pay less attention themselves.

The IIHS did say that, if used properly, LDW systems could save 7,529 lives per year.

Mercedes-Benz, which offers LDW as an option on several of its cars, thinks the study’s sample size was too small for the 10 percent statistic to be significant.

“Given the small sample size, the increase is not statistically significant,” Mercedes spokeswoman Donna Boland told USA Today. “We are confident as to the safety benefits of lane departure systems and would assume that further studies with a broader vehicle population would bear that out.”

So if LDW is a flop, what safety technologies do work? According to the study, forward collision avoidance systems and adaptive headlights are the most affective. These systems can brake a car autonomously to prevent a crash, and swivel headlights to see around corners, respectively.

“So far, forward collision technology is reducing claims, particularly for damage to other vehicles, and adaptive headlights are having an even bigger impact than we had anticipated,” said Highway Loss Data Institute vice president Matt Moore.

Blind spot monitoring and park assist, two other new safety technologies, had no discernible effect on crash rates, the study said.

All of the systems tested in the study are optional extras, and often cost thousands of dollars. Some are only available from luxury brands like Mercedes, Lexus, or Infiniti.

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