WASHINGTON—There may be a reason why people have trouble seeing while driving at night, and it’s not their eyesight. A new rating of the headlights of more than 30 midsized car models gave only one model a grade of “good.”
Of the rest, about a third were rated “acceptable,” a third “marginal” and a third “poor.” The difference between the top- and bottom-rated models for a driver’s ability to see down a dark road was substantial, according to the study released Wednesday by the Insurance Institute for Highway Safety, an industry-funded organization that evaluates automotive safety.
The LED headlights in the top trim level Toyota Prius V — the only one of 31 models tested to get the “good” rating — were able to illuminate a straight roadway sufficiently to see a pedestrian, bicyclist or obstacle up to 387 feet ahead. At that distance, the vehicle could be traveling up to 70 mph and still have time to stop.
But halogen headlights in the BMW 3 series, the worst-rated ones, were able to illuminate only 128 feet ahead. At that distance, the vehicle couldn’t be traveling at more than 35 mph and still have time to stop, according to the study.
That’s important because of the more than 32,000 traffic deaths last year, about half happened at night or during dawn and dusk when visibility is lower.
The reason for the big performance gap is that there’s a lot more to how well headlights help drivers see than merely the brightness of the bulb or even what type of bulb is used, said David Zuby, the institute’s executive vice president and chief researcher.
