Dusk and dawn are dangerous times to be behind the wheel. The road surface, pedestrians and other vehicles often are shrouded in shadow at these hours, but the sky still can be fairly bright. That contrast creates a problem—the light sky prevents drivers’ eyes from adjusting to the dark road. Meanwhile, the setting or rising sun sometimes is directly in our eyes…other drivers might not yet have turned on their headlights…and we might be feeling drowsy.
Here are smart ways to stay safe when driving at dusk or dawn…
Turn your headlights on before it gets dark. Don’t wait until night falls to use your headlights. Turn them on when the sun is low in the sky. Not only will your headlights provide additional illumination for you, they will make it easier for other drivers to see your car (and your taillights will be on so others can see you better from behind). And if drivers around you on the road notice that you have your headlights on as night approaches, it might remind them to turn theirs on, too, making it easier for you to see them.
Polish your headlights. Even the best headlight bulbs will not perform well if the front of the headlight is dirty, cloudy or otherwise blocked. Regularly wiping away dirt and road grime is a good start, but also use a headlight-restoration kit every year or two. These polishing kits, available in auto-parts stores and online for $15 to $25, can dramatically improve headlight performance by reducing the hazing, scratching and discoloration that can develop on the outside of headlights.
Clean your windshield inside and out. Dirt, dust and road grime on a windshield can refract light, creating glare. That glare might be only a minor annoyance during the day, but it can greatly reduce your ability to see the road at dawn and dusk when your eyes are struggling to cope with the lighting conditions. Use standard glass cleaner to thoroughly clean the windshield inside and out.
Get polarized lenses if you wear prescription eyeglasses. These lenses have an embedded chemical film that is likely to add at least $50 or more to the cost of your glasses, but it’s worth that price if you use the glasses for driving—polarized lenses dramatically reduce the glare in your eyes, especially in low-light situations and/or when the sun is low in the sky.
Wear sunglasses judiciously. If the sun is directly in your eyes, certainly put on sunglasses. Otherwise leave them off at dawn and dusk—they reduce the already limited light reaching your eyes at these hours. Besides, drivers sometimes forget that they are wearing sunglasses as dusk fades into night.
Helpful: Some drivers find that yellow-tinted glasses, which generally block less light than gray or green sunglasses, offer a nice compromise between wearing sunglasses and not wearing sunglasses at dusk and dawn.
Turn down your dash lights. Bright dash lights may make it easier to read gauges, but having these bright lights in your field of vision will further detract from your eyes’ ability to see a darkened dusk, dawn or nighttime roadway. Set the dash lights as low as you can and still read the dash.
Turn your head frequently to monitor surrounding traffic. During the day, you can track the cars around you on multilane roads out of the corners of your eyes. After night falls, other vehicles’ headlight beams reveal where these cars are. But at dawn and dusk, nearby cars can be a challenge to track—their headlights might not be obvious, and you might not be able to spot these cars out of the corners of your eyes—peripheral vision declines dramatically in low-light situations. Look side to side periodically to keep track of other vehicles on multilane roads.
Also, in neighborhoods, make a special effort to scan for pedestrians at dawn and dusk. People on foot can be very hard to spot at these low-light hours, and because there still is light in the sky, pedestrians might not realize that drivers cannot see them and step into their path.
Monitor your speed closely. During the day, many experienced drivers have a general sense of how fast they are traveling even without checking their speedometers. But this ability to estimate speed is rooted in their peripheral vision—their brains are noting the speed at which things are whizzing by in the corners of their eyes. As noted above, peripheral vision declines greatly in low light. Drivers should either check the speedometer regularly when sunlight is limited or, better yet, use cruise control or a GPS device that makes a warning sound when they exceed the speed limit.
Choose routes that are not directly into the sun. If you are traveling northwest at dusk, for example, you could choose a northbound road when the sun is right on the horizon, then switch to a westbound road after it sets so that you never have to contend with sunlight directly in your eyes. If you cannot avoid traveling east at dawn or west at dusk, choose a road that has tall trees and buildings alongside. These can block the sun as long as your route is not dead at the sun. If neither of these options is available, strongly consider pulling over until the sun is no longer right in your eyes. This is when the dangers of dusk and dawn driving are greatest.
Watch for signs of driver drowsiness in the vehicles around you. Drowsy driving doesn’t just happen late at night. Our brains start to release melatonin, a light-sensitive hormone that causes sleepiness, at dusk. If a car near you on the road seems to be having trouble staying in its lane or maintaining its speed, its driver might be drowsy. (He/she also might be drunk or distracted—the symptoms can be similar.) Put some distance between your vehicle and this one. Depending on the situation, you could drop back and follow at a distance…accelerate and pass…or pick a lane that is not adjacent to this vehicle on a multilane highway.
Monitor yourself for any signs of drowsiness as well. If you are having trouble staying in your lane, maintaining your speed or keeping your attention on the road, stop driving for the night or at least take a break for a cup of coffee.
Minimize distractions. Dusk and dawn driving require all of your attention. Pull over before doing anything that takes your focus away from the road—this isn’t the time to try to pick something up off the floor of the car or refer to a map. (Distractions are dangerous for drivers during the day, too, but the risks increase as sunlight decreases.) If conditions are especially challenging—say, you are driving toward the setting sun on unfamiliar roads—turn off the radio, too, so your focus is 100% on driving.
Increase your following distance. The less light there is in the sky, the longer it takes drivers to identify and react to potential dangers. One smart response is to drop farther back from the car ahead of you. The usual rule of thumb is to follow at least two to three seconds behind, but in low-light situations four seconds or more is prudent. (To judge this distance, start counting “one Mississippi…two Mississippi…” when the car ahead passes a road sign and stop counting when you pass it.)
