There are three main issues.
American drivers are saying they're getting blinded by car headlights, and it's not because headlight legislation has changed. Business Insider published an in-depth study of the matter, and the bad news is that it will take a few years to sort out.
If you need proof, look no further than the various online forums, communities, and social media pages dedicated to changing laws. There's an ongoing petition on change.org, and at the rate the numbers are going up, it will soon be one of the top petitions on the famous website.
Business Insider spoke to John Bullough, the program director at the Light and Health Research Center at the Icahn School of Medicine at Mount Sinai. Bullough is likely the foremost expert on the topic in the USA and is actively working with OEMs and third-party light manufacturers to find a solution.
But before a solution can be found, the problem needs to be identified. According to Bullough, there are three main issues.
According to Bullough, headlight misalignment is the most common problem.
"We actually did some measurements not too long ago and found that probably about two-thirds of every car had at least one headlight that was either aimed too high up, which is something that creates a lot of glare for other drivers, or too far down, which essentially limits their visibility," said Bullough.
According to Matt Brumbelow, a senior researcher at the IIHS, there is a gap in the federal regulatory system. There are equipment-based standards only. In basic terms, the headlight is certified before it's installed on the vehicle, and after there's no testing procedure to ensure it's aligned properly.
An entire headlight assembly can be off by 30 degrees if a single screw isn't tightened correctly. Ask anyone who has ever installed aftermarket lights on a Jeep Wrangler or NA Mazda Miata.
This issue is self-explanatory. Americans like big cars, which are only getting bigger and more popular. As cars get bigger and taller, the placement of headlights is higher.
Add to that the kind of vehicles sold in the USA. In 2021, 78.5% of new vehicles sold were trucks or SUVs. Looking at these figures, the placement of headlights should cancel each other out, but using that logic ignores all the existing cars out there. The average vehicle age in the USA is 12.2 years, which takes us back to a time when the split between sedans/hatches and SUVs/trucks was 50/50.
Bullough says that because of this growing need to go bigger, the band of light is much higher, blinding people in cars that are lower down.
LEDs are the new norm, which means manufacturers have moved away from the familiar yellowish light provided by halogens. Even though LEDs provide much better lighting, the human eye is susceptible to the blue wavelengths within the shine of an LED bulb.
Once again, there's a problem with outdated legislation, and this time with how light is tested. The equipment used to test candlepower (light intensity relative to the light emitted by a candle of a specific size) is not sensitive to the blue hue. It only measures a much higher light intensity, not considering the effect on the human eye.
A solution has been available globally for years, but the National Highway Traffic Safety Administration (NHTSA) has lagged in approving it. Adaptive lighting can adjust the LED beams to avoid blinding not only other drivers but cyclists, bikers, and pedestrians.
While the NHTSA finally lifted the ban on adaptive lights in 2022, the rules and regulations are highly complex and don't match up with legislation drawn up in Europe many years ago. As a result, many manufacturers don't bother. The new Audi Q8 e-tron comes standard with advanced adaptive headlights in Europe, but the feature is unavailable in the USA.
"We're still not aware of any [adaptive headlights that] are available in the US, so it might take a few years for the manufacturers to make sure that their high beam or their adaptive driving beam technology meets the requirements that the NHTSA has released," said Brumbelow.
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