You’re being lied to. I know, that sentence sounds like conspiracy theory clickbait. But the lie I’m talking about isn’t coming from the government, Hollywood, NASA, the educational system, or a cabal of doctors. It’s from your own brain. Next time you drive at night, your brain is going to tell you that you can see better than you actually can.
Vision has two jobs when you drive; your ambient vision takes care of lane-keeping (helping you know where you are), and your focal vision identifies objects and obstacles up ahead. The problem is that we don’t need a lot of light for lane-keeping; our headlights are more than adequate. But they fall short for obstacle recognition, and sometimes by a lot. Your ability to safely travel in your lane leads you to believe that you can adequately see and respond to any obstacle up ahead in the road. That’s the lie.
Headlight tests have found that low beams provide a lighted distance of between 300 and 450 feet, depending on the type of bulb, and high beams reach up to 500 feet. That would correlate with a maximum speed of 39 mph at the low end and 55 mph at the top before overdriving your headlights.
But that’s an overly optimistic result based on ideal circumstances. Even if headlights reach that far, drivers don’t notice obstacles at that range. When a pedestrian in dark clothing approaches a roadway from the right, the average driver spots them at 150 feet. When approaching from the left, visibility distances are cut in half. If you’re puzzled about the difference, it’s easier to spot pedestrians approaching from the right because car headlights are aimed slightly toward the right to reduce glare for oncoming traffic.
We can calculate an estimated vehicle stopping distance for given speeds. If we use a perception-reaction time (the time it takes to see and then respond to a hazard) of 1.5 seconds (the standard for an attentive driver), at 25 mph it takes 85 feet to stop, at 35 mph it’s 135 feet, at 50 mph it’s 230 feet. Those distances only get longer if road conditions aren’t ideal or if the driver isn’t looking at the road when the hazard emerges.
Conceivably then, even at 25 mph a driver might not spot a pedestrian approaching the road from the left until it’s too late. And think about all the rural roads with 50 mph speed limits. You’re not likely to encounter pedestrians, but if a deer wanders out in front of you, both the deer and your fender don’t stand a chance.
Is the problem our headlights? One report stated that “headlights found in U.S. vehicles fall short on safety.” But that’s not exactly correct. Our headlights fall short of illuminating the road at the speeds we’d like to drive. If we drove slow enough, our headlights would be sufficient. However, many drivers would probably find that speed unacceptable.
What about making headlights brighter? In the movie Joy Ride, the lighting crew replaced the vehicle headlights with aircraft landing lights for the nighttime chase scenes. Great on a closed movie set, but not for oncoming traffic on a public road. We’re already at the limits set in law for the maximum brightness of headlights.
I’m not proposing 20 mph nighttime speed limits. My point here is that our headlights aren’t up to the task of illuminating hazards in the road at the speeds we typically travel. Knowing that driving at night is a sub-optimum condition, it’s up to us as both drivers and pedestrians to make wise decisions.
Vehicles today so damn expensive there shouldn’t be any issues with anything on them regardless what kind of vehicle you drive special specially headlights I got chemicals today that you could put on the lens, but I have to found anything that works? Point is it’s expensive these vehicles are there should be no issues with any of them regardless what you drive
I know that’s what your source says, but 500′ is way short of what high beams travel. They easily go 1000 feet, and many easily go twice that far. Low beams are limited by their modern beam cutoff patterns, and may have even less than 350′ of the brightest area, and that’s likely more of an issue.
Also, the linked “fact sheet” source claims 64% of adult drivers never use their high beams at night. I’d guess that’s because most people live in urban or suburban areas where there’s street lighting. If you get out into more rural areas nearly 100% of drivers use their high beams at night if not near other traffic.
You’re right that high beams throw light farther than 500 feet. I believe the study (and I could have been more clear about this) was referring to the distance at which a driver would spot a non-reflective object (like the typical pedestrian in the PNW).
And coincidentally, I experienced this a few days ago. I was driving at night and thinking about how far my headlights reach because I’d just written this, and all of a sudden I spotted a pedestrian on the edge of the road, maybe 200 feet away. I could see the stripes on the road for much further, but I wasn’t expecting a pedestrian there and didn’t notice until I was quite close.