A 2022 regulation allowed the technology in the US for the first time, but more than a year later, no vehicles with it are available for sale.

At the same time, Americans may be experiencing more glare. Over the past two decades, vehicle headlights have transitioned from primarily warm yellowish halogen to cool bluish LEDs, to which human eyes are more sensitive. Newer vehicles are getting taller, so oncoming headlights are more likely to be at eye level for drivers of small cars. And few states annually check for headlight misalignment, which can beam into the eyes of an oncoming driver.

That combination of risk factors makes it all the more important to get adaptive driving beams on US roads, auto safety researchers said. But the new rule’s testing requirements are so detailed and cumbersome that automakers say they would have to redesign systems, potentially delaying implementation for years, despite already-available European technology. security researchers warned regulators against create that kind of red tape years ago.

The National Highway Traffic Safety Administration said in a statement that its lighting standard «has long balanced the visibility needs of drivers while limiting the glare of others.»

But the agency couldn’t just adopt the European rule because the US and Europe approve vehicle technology in different ways: Automakers test their own vehicles to meet US safety standards, while regulators test vehicles in Europe. The United States and Europe also have different legal processes for approving new technologies.

“NHTSA carefully considered existing standards [European] regulation during the rulemaking process,” the agency said. «In areas where that regulation lacked objective and measurable performance criteria required for the self-certification system in the United States, the agency adopted performance requirements to ensure the safety of all highway users.»

‘The capacity is already there’

Many newer American headlights automatically switch between high and low beam, improving nighttime visibility. But adaptive road beams can take those improvements much further, using floodlight that constantly adjusts to reduce glare by illuminating occupied areas of the road less and unoccupied areas more. Research shows that they make it much easier for drivers to spot pedestrians.

Getting approval for this technology in the US took nearly a decade. Toyota first applied to the agency to allow adaptive high beams in 2013, a year after they were introduced in Europe. Many NHTSA safety standards can take that long, but the agency has been investigating glare since at least 2005 and began receiving consumer complaints about it as early as 2001.

As the US adaptive high beam rule inched its way through the regulatory process, automakers were eager to offer the feature to American drivers. Audi, the first automaker to use the technology in 2012, began including adaptive high beam systems on some of its models sold in the US in 2014, anticipating the regulation change but leaving them disabled.

Adding the systems wasn’t difficult, as nearly all Audi models have them as an optional feature, and in Europe about half of Audi vehicles are sold with the technology, said Filip Brabec, the company’s senior vice president of product management. . “For the US specifically, we have over 150,000 cars on the road today that could have it if we just turned it on. … The capacity is already there.”

“It’s very frustrating,” he said. “We have technology that has been proven in many countries around the world, and we would really like to bring it to the US.”

NBC News contacted five other major automakers to ask if they sell US vehicles with inactive ADB capabilities. Volkswagen Group, Audi’s parent company, said it has 14,000 Volkswagen-branded vehicles in the US market. Ford and Honda said they don’t have any in the country and two others declined to comment or did not respond.

Street signs on a dark road reflect light from a test vehicle’s adaptive driving beams.nbc news

Industry experts such as the SAE (formerly the Society of Automotive Engineers), which the regulators consulted when writing the new rule, recommended that the US try to match the standard already in use as closely as possible.

The final rule explained the volume of testing as necessary to «meet the need for safety» and said it had deviated from the SAE recommendation because it «does not adequately address the safety needs of visibility and glare prevention.»

Several industry groups and companies, including Ford, Honda and Volkswagen, have asked NHTSA to reconsider its requirements, and the Alliance for Automotive Innovation, a trade group representing automakers, has asked the agency to do so.

“The final rule contains several requirements that are not practicable or unreasonable,” the group wrote in their petition. «If not adhered to, parts of this rule present themselves as an obstacle to the deployment of this important security technology in the US market.»

NHTSA is still evaluating the reconsideration petitions. For now, automakers say they don’t have a clear timeline for when they’ll be able to introduce the technology to the US When they do, it’s likely to cost much more than current systems.

‘A lot of glare’

Adaptive driving beams can go a long way to making night driving safer, but there are some things they can’t fix, safety researchers said.

AAA’s Brannon said the new rule is «a step in the right direction» but doesn’t match European standards in part because the US has a much lower maximum light output for high beams, a level established decades ago. “This technology could allow for more light output because it shields things that shouldn’t see light at all. So it would have been a good time to improve light production standards.”

NHTSA «is not aware of any studies or data showing that increasing upper beam intensities would improve safety and that doing so would likely increase glare levels on highways in the United States,» an agency spokesperson said.

Despite the lack of change, veteran drivers are likely to feel that headlights have gotten brighter in recent decades as halogen headlights have been replaced by more efficient LED lights.

“The light looks so much brighter,” said John Bullough, program director at the Mount Sinai Center for Light and Health Research. «Our eyes are actually more sensitive to the bluer light that these lights can produce, compared to yellow light or light from halogen lights.»

But glare is more a function of where the headlights are pointed, rather than how bright they feel. And as taller vehicles like pickup trucks and large SUVs gain popularity, those headlights are more likely to shine into the eyes of drivers on lower-mounted vehicles.

For Bullough, misalignment is the biggest problem. His research has found that most vehicles on the road have at least one badly aimed headlight.

“Headlights are not like a flashlight, where they just throw a beam of light, there is a very sharp horizontal cut. So there is a line below which the headlights are very bright,” he explained. “When you’re 100 feet away, a small change in the way the headlight is pointing can make a big difference in putting your eyes on that bright part of the headlight beam.”

John D. Bullough lights a lamp to show the power of an LED in the eye.
Light researcher John Bullough tilts a headlamp in a demonstration of how the lens changes glare.nbc news

Only 15 states require annual or biennial passenger vehicle inspections, and NBC News found that of those, 10 check headlight alignment. The five states that do not check alignment check other headlight functions instead, according to the inspection agencies. One of them, Hawaii, just passed a bill that would add headlight alignment to its inspection requirements; the measure now awaits the governor’s signature.

Two other states, New Jersey and Mississippi, stopped requiring mechanical safety inspections of passenger vehicles in the last 13 years. Old New Jersey inspections included headlight alignment.

Headlight alignment is fairly easy to check and repair, Bullough said, and any mechanic should be able to do it. But if a driver isn’t in a state that requires that check, he has to know how to ask for it.

Misalignment can occur with normal wear and tear, but even newer vehicles can have misaligned headlights, because federal law does not require manufacturers to check alignment once headlights are mounted on vehicles. The Insurance Institute for Highway Safety, which tests headlamp aiming annually, has repeatedly asked federal regulators to add the tests to their requirements.

“If there is a single problem with the regulation that we discovered [by testing] that needs to be fixed, it’s this targeting problem,” said Matthew Brumbelow, senior research engineer at the Insurance Institute for Highway Safety. He has seen improvements in headlight aiming in the years since they began testing it, but said a federal requirement would be much better.

A NHTSA spokesperson said the agency has begun investigating a federal requirement, after the 2021 Bipartisan Infrastructure Act directed it to develop a standard to «ensure headlights are correctly aimed at the road.»

For now, said Bullough, the lighting researcher, the best advice for drivers is to check the alignment of their vehicles’ headlights and, if facing glare from oncoming headlights, slow down and try to look to the edge. right outside of light. way until it is reduced.

The one thing not to do, he said, is wear sunglasses at night to try to cut down on glare. “The problem is that we are already dealing with very low light levels outside at night. And that will make it much more difficult to see a pedestrian or some other object on the road.»