Are headlights brighter? No, but they can feel like it

Daylight lingers longer thanks to the clock skipping an hour recently.

But a neighbor’s new car has Fabian Borowiecki of Everett looking for shade.

“At night those headlights literally light up the entire block we live on,” he wrote to The Daily Herald. “Backing into their garage, it’s like a spotlight turned on, so much so that the house five away gets all lit up.”

He’s noticed other vehicles seem like their beams are too luminous as well. Oncoming vehicles that “come awful close to being blinding” when he drives at night led him to ask about the rules for headlight brightness.

Former Street Smarts columnist Melissa Slager wrote about headlights in 2015 after a reader asked about the prevalence of blue-hued lights that hurt her eyes.

Other writers, including at The Columbian, Slate and The New York Times, have tackled the issue as well in recent years.

What was true then still is.

Stock headlights aren’t brighter, technically.

“They just aren’t,” University of Michigan Transportation Research Institute associate professor Mike Flannagan said.

He has studied driver vision for most of his 30-year career. Headlights are a major element of his research.

Low beam headlights are a compromise between not adequately illuminating a roadway at night at speeds faster than 45 mph and limiting glare for other road users, Flannagan said.

Headlight regulations haven’t changed much in the past decades, Flannagan said. Their minimum and maximum outputs are well codified federally.

The Washington State Patrol lists the state’s lighting laws online which generally conform to federal standards.

That’s why GMC is recalling 740,000 Terrain SUVs across the country. More technically, it’s an issue with reflections in the headlight housing, as The Associated Press reported in March.

Instead of headlights being brighter, it seems to be a combination of aging eyes, the way human eyes perceive more modern headlights, and how drivers can adjust their angle.

Older drivers need more light to see at night, according to the American Optometric Association.

High-intensity discharge headlights, called HIDs, use xenon gas and electricity to produce light. The light from them and light emitting diodes (LEDs) can appear blue.

In studies, people report feeling like they see better with blue-white headlights, though tests don’t show an effect supporting or detracting from that claim, Flannagan said. That hue also doesn’t have a measurable result on glare.

In the 1990s auto manufacturers changed how headlight position can be adjusted. It means drivers can direct the light angle, which can be off after normal bumps and jostles from road use.

“Even if it’s off by a degree, it’s too much,” Flannagan said.

For drivers who experience sharp glare at night, there’s not a lot they can do. Flannagan doesn’t recommend glasses marketed for curbing glare.

“Ever since there have been headlights, there have been people selling night driving glasses despite the lack of evidence they do anything except harm,” he said.

Instead, there may be a nationwide technology change ahead.

Adaptive driving beams are the next big thing for vehicle lighting tech. These new headlights read light and shine more brightly in dark areas and dim for well-lit spots. On a two-lane road, a driver’s vehicle automatically could shine high beams on a deer ahead while keeping low beams on an oncoming vehicle.

Hopefully that can curb the glare Borowiecki and others experience on the road and in their home, though that change will be up to the market.

“It really is annoying driving down the street and thinking that a 737 is coming at you with all it’s landing lights on,” Borowiecki said.

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