Report: How Headlight Glare Became Such a Big Problem

If you’ve been driving for a while, you’ve undoubtedly noticed that headlamps have gotten so ludicrously bright that they’ve become a safety issue. Consumer complaints about on-road blindings continue to climb and, in the absence of any true regulatory response, a grassroots push back has begun.

The problem stems from many issues. Light-emitting diodes (LED) and high-intensity discharge (HID) headlamps are significantly brighter than the units used in previous eras. Older halogen lamps simultaneously carried a more natural yellow hue that was easier on the eyes than the harsh blue-white offered by LEDs. Today’s vehicles are also more likely to be larger, with a penchant for forward illumination to be mounted higher. While this often ends up being an advantage for the person driving in the dark, it has created problems for approaching vehicles hoping to maintain their vision.

Often tolerable in urban settings featuring substantial ambient lighting, modern headlamps are frequently blinding to oncoming traffic in an otherwise dark rural environment. This is especially true if you happen to be driving a vehicle situated closer to the pavement and come up against an SUV or pickup with a higher ride height. The issue has actually gotten so bad that the Insurance Institute for Highway Safety (IIHS) has actually started to make it part of its testing protocols.

But the problem here is that the IIHS and other safety groups likewise believe that enhanced forward illumination helps people avoid accidents. The reasoning for this is sound. Being able to see the road ahead is invaluable, therefore being able to see more of it is objectively better. However, studies are simultaneously suggesting that modern headlights may have gotten so bright that they’re probably contributing to accidents.

Your author has long griped about touch-based infotainment and electronic driving aids being a double-edged sword in terms of promoting roadway safety. But it’s the intense brightness of oncoming headlights that I most often hear my friends complaining about — and for good reason. According to the National Highway Traffic Safety Administration (NHTSA), the average headlight brightness of new models has more than doubled since 2010.

However, despite most safety groups being aware of the blinding effect, government regulators around the world have been trending toward demanding more forward illumination. Automakers also want to continue using LEDs because they are smaller and infinitely more customizable than prior technologies.

The Ringer, an outlet typically focused on popular culture, reached out to the founder of a subreddit dedicated to compiling complaints and data points about modern automotive headlights to learn more about how the problem has gotten so bad. Forum founder and web developer Paul Gatto, along with former engineer Victor Morgan, explained to the outlet that the real issue isn’t so much about lightning technology but the way in which society has gone about handling it.

The duo have effectively made solving the headlight problem (and forum) their primary hobby and served as a jumping off point for the outlet to explore the issue more thoroughly. Despite not being a vector for automotive reporting, it’s probably the best article I’d read on the subject of headlight safety in years.

From The Ringer:

John D. Bullough, a program director at the Mount Sinai Light and Health Research Center, has been studying light and its ramifications on health for the past 30 years, and he’ll tell you that the difference between older light sources and LEDs is night and day. “The first 20 years or so, [lighting] technology was very stable,” he told me over the phone. “In other words, you had incandescent light bulbs at home, and you had fluorescent lights in your office and sodium lights on the streets, and nothing really changed very much. And then, suddenly, the last 10 years of that 30 years have been a whirlwind because of LEDs. I mean, they’ve changed everything. Everything is LED. There essentially aren’t light bulbs anymore.”

LEDs offer benefits over older light sources, which is why they’ve been fast-tracked into near-universal use via government-mandated performance standards. They last longer and require less energy, making them more environmentally friendly, and are more customizable, making them suited for endless purposes. But LEDs are fundamentally different from what came before them—the light can be carefully aimed as opposed to emitted in all directions—and they’re vastly more powerful. And as they were rolled out en masse at a rapid pace, any potential repercussions would have to be discovered on the fly.

“We’re all like human experiments,” said Mark Baker, when I called him to talk about his nonprofit, the Soft Lights Foundation, the mission of which is to advocate “for the protection of people and the environment from the harms of visible light radiation emitted by products that use light-emitting diodes.” Baker’s concern is with the broader integration of LEDs in society, but he shows up regularly in the headlight world, having recently organized a petition that gathered nearly 60,000 signatures demanding that NHTSA limit headlight intensity. Unlike Morgan and Gatto, however, this isn’t a nights and weekends gig for him.

Limiting forward illumination on cars could likewise have some negative ramifications and your author recommends we always be skeptical of knee-jerk regulations. But it’s glaringly obvious (ha) that headlight brightness has become an issue for drivers.

Baker said that started the Soft Lights Foundation after feeling light the daytime running lights that have similarly been equipped to modern vehicles were hypnotizing him in 2016. It was his assertion that even the dimmest LEDs were becoming distracting. As they became more prevalent, he had a full-on breakdown due to being mildly autistic and prone to sensory overload. Driving at night effectively became impossible for the man since he would feel immediately overwhelmed, while the implementation of LEDs elsewhere in society further encouraged him to stay home.

By 2021, he decided that there needed to be a group for people who were diagnosed with epilepsy, photophobia, migraines, lupus, or autism as nighttime illumination grew harsher. Baker currently works with other such organizations to encourage the NHTSA to think more critically about the issue — noting that the federal safety rules surrounding headlamps seem to change to accommodate manufacturers more than drivers.

The way in which LEDs throw light also allows manufacturers to game any brightness limits in regard to how they’re currently measured. Chris Trechter, an engineer who previously worked for Magna International, told The Ringer that “there are giant [regulatory] loopholes that allow you to throw basically unlimited light,” provided you’re using LEDs and managed to meet the baseline safety standards. By specifically darkening the relevant testing areas, automakers can effectively make modern headlights as bright as they want in the real world.

But why is it even happening? Modern headlamps are so exceptionally bright that I’m not aware of anyone that wants more forward illumination on their daily driver.

The article speculates that the IIHS, a nonprofit funded by insurance companies, has become the de facto leader in determining safety ratings and automakers very much want to be able to claim that they’re getting top marks for advertising purposes. But we’ve covered in the past blind spots within IIHS testing. It often glosses over how the sizing disparities of modern vehicles change accident survivability rates and it’s heavily encouraging the implementation of more connected driving aids that remove control from drivers, while simultaneously monitoring them to hold them accountable, specifically because it’s what insurance groups want.

But the IIHS has more recently tried to address the issue of glare and has even started to incorporate it into some of its testing protocols. “[While] you can’t get a good rating and have super high glare,” explained Matthew Brumbelow, a senior research engineer with the IIHS, “you also can’t get a good rating and have a dim headlight that doesn’t glare anyone but also is too dim to help people avoid crashes on the road.”

Brightness still plays the greater role in terms of what the IIHS deems safe, however. Gatto and Morgan are trying to prove that this doesn’t make sense anymore. They’re arguing that brighter headlights only pay off when you’re the only person on the road and have become a liability whenever cars are required to share space.

It’s something anyone who drives on a regular basis instinctively knows. But developing a novel testing protocol that takes into account relative brightness and varied headlamp positioning is much tougher. Safety testing needs to be repeatable to provide good data. However, headlamp blinding occurs at different rates based on numerous factors. The height of the automobiles involved, the position of the headlamps, how the individual LEDs are aimed, how dark it happens to be outside, and the angle at which the two vehicles approach each other are all relevant factors. Many drivers don’t even properly align their headlights and plenty of vehicles have rolled out of the factory with the same problem, too.

Needless to say, it’s a lot to deal with.

The NHTSA seems content with things as they are and toldThe Ringer that aftermarket LED conversions are probably the biggest issue, as they’re often not properly aligned and even illegal in some regions. This simultaneously displays how government agencies often protect OEMs at the expense of aftermarket companies and makes the above a problem for local law enforcement — who likely wouldn't be able to tell the difference between a bright factory headlight and some poorly done aftermarket job anyway.

Adaptive headlamps, formerly illegal in the United States, have been posited as one possible solution. Sensors in a vehicle could pick up oncoming traffic and automatically redirect beam arrays in a way so as to limit how much is directed at other motorists. But this is an expensive solution and one that’s eventually going to break, resulting in more expensive repair bills or broken systems that the owner never bothers fixing. It also fails to address the general brightness of LEDs headlamps and running lights.

The rest of the piece is largely speculative and dives into ways to address the issue. While there’s not much of a consensus within the industry, which seems woefully out of touch these days, there are a lot of familiar excuses being thrown around. Some even alleged that the blinding phenomenon is simply over-hyped and a figment of critics’ imagination. Others suggested that the fact that modern controls have become less intuitive and that many drivers may simply be unwittingly leaving their high beams on.

However, the biggest takeaway from the piece should be how absolutely insane our regulatory system works. Automakers are lobbying from one thing, often getting what they want from the government, while the concerns of the affected citizens go unheard. The largest number of complaints filed with the NHTSA in recent years have pertained to headlight glare, yet the agency frequently acts as if they’re no problem. Meanwhile, industry safety standards are being set by insurance companies with a vested interest to protect their business above all else.

It may be a small consolation. But it’s nice to know that there are consumer advocacy groups out there at least trying to solve the problem.

[Images: Pankaj_Digari/Shutterstock; Flystock/Shutterstock; CC7/Shutterstock]

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