From the time the sun sets until the time it rises again in the morning, anyone who has to head out on the road will be driving in extreme darkness with very limited light available. Any time you have to drive without an adequate amount of lighting, there will be varying difficulties from those you would face when driving during the daytime in optimal lighting.
Everything looks different when it is dark, and there are a variety of reasons for this—one such reason is our eyes dilating differently in the dark than they do in the light and another cause is the reflecting glare of lights surrounding us while on the road (from other cars, streetlights, and lights reflecting off signs). A driver’s perception of the road and their reactions are also different when driving at night than compared to when they are when driving during the day.
According to the American Academy of Ophthalmology (AAO), our pupils dilate more in the dark in order to pull in more light. To process this light, we use the rods and cones of the eye. Rods are only able to see black and white and are more sensitive in the dark. Cones rely on daylight or other lighting to process colors and see specific details. This means when you are driving in the darkness your eyes will be relying on rods more than cones, making it harder to see colors and details.
Additionally, the AAO points out that there are many people who are challenged with nearsightedness and astigmatism, which for many can worsen at night. Nearsightedness can cause objects on the road to be less clear and sharp than what they would look like during the day. Astigmatism can cause you to have more difficulty with your peripheral vision and make it harder to accurately perceive depth of objects. Even people with generally good vision can have trouble driving at night.
Despite all the difficulties driving at night can present with your vision, there are still some things you can do to make driving in the dark less difficult.
Here are a few tips you can use to help improve your safety when driving on the road at night.
The first thing you should do is dim your interior lights on your vehicle’s dashboard low enough to where they are still visible but not distracting. Many newer vehicles automatically switch over to dimmer lighting around sunset.
Some vehicles have rearview mirrors that dim the headlights reflecting in them—but not all do and side mirrors are often not equipped. If you are driving in front of someone in a larger vehicle, who has LED lights, or is using high beams or fog lights, then their lights may be causing you visibility issues. Adjust your mirrors to prevent reflecting their light into your eyes. Just remember to readjust in the morning.
It is not uncommon for individuals with great vision to have difficulty seeing at night—like seeing sunbursts around lights or not being able to properly judge the depth between the car in front of their own. This can be caused by astigmatism. Check with your eye doctor about prescription glasses with an anti-reflective coating. Increasing the space you maintain between yourself and other vehicles, breaking early, and reducing your speed can all help improve your reaction time and reduce your risk for a collision.
Of course, when you are driving in the dark you want to take advantage of any light you can. But sometimes lights in the nighttime darkness can hurt you just as much as they help. To make sure you are using light wisely, dim interior lights and adjust your headlights so they are properly aimed for optimal visibility of the road.
You will also need to make sure you are not becoming distracted or blinded by the headlights of other drivers or other lights on the road. To do this, avoid looking directly at the lights or staring at them for too long.
This one should be obvious, but it is easy to become distracted or even drowsy when driving at night. The National Sleep Foundation recommends staying off the road between midnight and 6 a.m.—the time when most drowsy-driving accidents occur. If making a long drive, take breaks to at least every two hours whenever possible.