In an era of smart cars and technological advances, many cars are left with one glaring problem: their headlights. A new study by the Insurance Institute for Highway Safety (IIHS) tested 31 popular car models and found only one met “good” standards for headlight safety. 19 cars met “marginal” or “poor” standards, and 11 met “acceptable” standards. Previous safety studies have shown that most crashes in urban areas and about half of the crashes in rural areas happen at night.
Researchers at IIHS used a special device that measures light output to monitor headlights in five scenarios: traveling straight, right and left sharp curves, and right and left gradual curves. IIHS also took into account the negative effects of overly bright headlights on oncoming drivers.
The measurements from the scenarios were compared to a hypothetical ideal headlight reading, and certain measurements were given more weight. The researchers gave extra weight to the measurements for low beam lights versus “brights” or high beam lights since low beams are more commonly used. Some cars with high-beam assist, or the ability to automatically switch between high and low beams based on oncoming traffic, were also given extra weight.
Researchers also gave extra weight to readings on straight roads versus curved roads because 81% of fatal urban crashes and 67% of fatal rural crashes occur on straight roads.
Though the study included only 31 vehicles from 21 different car companies, the IIHS gave a total of 82 headlight ratings to account for the different types of headlights that single car models can have. The BMW 3 series earned a “marginal” rating, but consumers can choose to purchase the car with halogen headlights, which would earn the car the worst spot on the list of all 82 headlights. Using halogen headlights, drivers could go no faster than 35 mph to have enough time to stop for a sudden obstacle.
The best-rated car, and the only car to earn a “good” rating, was the Toyota Prius v with LED lights that allow drivers going 70 mph enough time to stop for a sudden obstacle.
The researchers did note that consumers can turn their car's poor rating by adjusting the headlights themselves. Often the problem with less visible headlights is simply the aim of the lights. But most consumers do not adjust their car's headlights, so the cars in the study were tested with factory settings.
The study highlights the wide variety allowed in government standards for headlights. New technology allows for safer headlights in all cars with features like brighter LED bulbs or curve-adaptive headlights that swivel with the steering wheel.
Drivers can follow these headlight safety tips to stay safe at night:
Use high-beam headlights as much as possible
High beam headlights dramatically increase the scope of the driver's view. Be careful of oncoming traffic because high-beam lights can blind drivers. If an oncoming driver doesn't turn off their brights focus your eyes on the right side of the road as you pass.
Use your mirror
Change your rearview mirror to night settings by flipping the lever at the bottom of the light, this will reduce glare.
Dim your dashboard lights
Bright dashboard lights detract from forward vision.