A high beam is a type of automobile headlight. The headlights in your vehicle have two modes: low-beam and high-beams. The low-beam mode produces a less intense light that provides a nighttime down-the-road view of about 200 to 300 feet or the approximate length of a football field.
It may seem like a lot, but if you’re traveling at 60 mph, it takes just 3.4 seconds to cover that distance. Your high beams, which are typically activated either by pushing or pulling the turn-signal stalk, are more powerful: They project light about 350 to 500 feet, depending on your lighting system’s specifications.
High beam headlights should be used at night, whenever you’re unable to see enough of the road ahead to drive safely. Low visibility at night can be scary for even the most experienced drivers. Why is driving after dark more dangerous? 90 percent of a driver’s reactions depend on acute vision, including depth perception, color recognition, and peripheral vision, all of which become severely limited at night. High-beam headlights shine at an angle to illuminate the road 350 to 400 feet ahead or about twice as far as low beams.
What High-Beams Can and Can’t Do?
Isn’t more light always better for nighttime safety? Why not simply leave your high beams on and enjoy the brightest, longest-range view? First, high beams are actually less effective in certain weather conditions. And second, it’s not safe, because we share the roadway with other drivers.
While you see more and farther under most conditions in high-beam mode, your powerful blast of light actually reduces the visibility of oncoming traffic (sometimes for a significant interval of time). This situation is like staring into a flashlight in a dark room.
You can see the blazing light but little to nothing else around it. Imagine traveling on a dark two-lane road at 50 mph with oncoming traffic. The closing speed between the vehicles is approximately 100 mph. And the closer the vehicles get to each other, the less the surrounding area and other traffic are visible.
Has this ever happened to you? If so, you know how important it is to know when to use your high beams. The intense oncoming light is painful to the eyes and mentally discomforting; you simply can’t see much for a couple of precious moments. And second, motor-vehicle laws in most states require you to switch off your high beams and refrain from flashing your high beams within 500 feet of other traffic.
Should You Flash Your Lights?
But what if another driver fails to dim their brightness? Most driving manuals recommend focusing your eyes on the right shoulder and its white line as you pass. Why not vigorously flash your high beams at them? Flashing, unfortunately, is an ambiguous form of communication.
Are you angry, being rude, or warning others about a speed trap, a deer crossing the road, or an accident behind you? Flashes are easily misinterpreted by other motorists and police. Although Florida has ruled that flashing your lights is a form of free speech, Michigan ruled it’s also legal to flip off an officer, law enforcement in other states may consider flashing your lights a reason to pull you over.
When to Use High-Beams and When not to?
Isn’t more light always better for nighttime safety? Why not simply leave your high beams on and enjoy the brightest, longest-range view? First, high beams are actually less effective in certain weather conditions. And second, it’s not safe, because we share the roadway with other drivers.
1. Low visibility in urban areas
You may find yourself driving on a dark city street, on an unfamiliar road, or in a construction zone. It’s unnerving to realize that you’re unable to see the road ahead. When your vision is impaired, slow down. If there are no other vehicles nearby, turn on your high beams.
Your high beams will also protect pedestrians and bicyclists who may be on the side of the road or crossing in front of you. In urban areas, state law typically requires you to dim high beams within 300 to 1000 feet of approaching vehicles. You must also dim them within 200 to 300 feet of vehicles you’re following, especially at stop signs and traffic lights.
2. Interstate highways
Visibility on some interstate highways or they’re on- and off-ramps may be poor. There may be long stretches of road that are only illuminated by your headlights. In those low-visibility conditions, use your high-beam headlights to increase your viewing range.
However, dim your high beams when you’re near other vehicles, even on divided highways. Check with your local DMV for the exact distance your state requires. When you’re approaching another vehicle from behind on an interstate highway or at a toll plaza or rest area, always dim your high beams to avoid blinding the driver.
3. Rural areas and country roads with few streetlights
On rural roads and open highways, street lighting may be sparse, which can make driving more treacherous after dark. Your high-beam headlights will let you see farther down the road. In rural areas, high beams also help you avoid hitting animals, bicyclists, or pedestrians taking a late-evening stroll.
While country roads may appear deserted, be prepared to quickly dim your high beams for approaching traffic or when you approach another vehicle from behind. By dimming your high beams, you’ll be protecting other drivers.
When not to use your high-beam headlights
Never use your high-beam headlights while you are driving in fog, rain, or snow. In such conditions, they can make your vision even worse. High beams will shine directly into the fog or precipitation, which will reflect the bright light back to you.
During snowstorms, snowflakes and ice crystals will reflect even more light back to you. The dangerous result is a wall of glare, which will make it even more difficult for you to see the road.
How to Change from Low-Beam to High-Beam
Different makes and models of cars have different methods for switching from low-beam to high-beam and back. In most cases, the mechanism is built into the lever next to the steering wheel, where the headlights are turned on and off. Alternatively, high beams may be activated by a small button on the left side of the driver’s floor.
To change from low-beam to high-beam, simply turn on the headlights and then press the lever with your hand, or activate the floor button with your foot. To change back, simply repeat this action. In some models with lever-activated high beams, you can press the lever in one direction to flash the high beams once, and pressing in the other direction turns them on permanently.
High-Beam Assist Technology
Some newer models of cars have a technology called high-beam assist. This feature automatically adjusts the headlights to the correct setting, so you do not have to do anything. Until this technology becomes standard on all cars, cultivating a habit of using high-beam and low-beam headlights correctly will make you safer and may help you avoid a ticket.