Driving in poor visibility conditions is more than just an inconvenience. According to the U.S. Department of Transportation, approximately 21% of yearly car crashes are weather-related. In such situations, fog lights can be and they are designed to be a powerful supplement to the already existing lighting system – they replace or illuminate areas of the road which are not yet present in the field of vision of the car’s main headlights. 

Not to be mistaken with being drunk, which is a different type of fogginess, fog blindness occurs when there’s too little light to reflect off the object one wishes to see or observe. 

The human eye can generally see pretty far, depending on multiple factors, such as Earth Curvature, visual acuity, and many other factors. However, despite being able to see the Moon from 384.400 km away, there are some particular conditions in which we can’t even see 1000 meters away from us. 

Why is fog risky for drivers?

This brings us to the question – why is fog hindering our driving experience? Because it is made of water, it reflects light differently than normal weather conditions do. Since an object has a certain brightness when we look at it directly, fog appears to be much darker and further away, which confuses drivers due to the aforementioned reason. 

The primary source of this misleading impression is water droplets within the fog, which are constantly in motion, but always produce just enough light reflection to create that illusion of blackness in front of your eyes.

This dark fog is a combination of light from your headlights and fog lights reflecting off the air’s moisture. While you may find this curious phenomenon perplexing, there are many other people whose spinning wheels have led them to spin right into this seemingly paranormal mist.

Driving is a visual experience as much as a cognitive task – it requires low response times, adjustment to one’s environment, analytic skills to determine which is the best course of action during hazardous road conditions, plus attention flexibility to shift from one cue to another. Pedestrians, road signs, other cars, the annoying colleague who missed the deadline, and all the other objects present in traffic can impact a driver’s actions.

And that is just the casual version. Once the visual perceptions are impaired, drivers will tend to react slower, act based on the faulty representation of what they encounter on the road, or inadequately anticipate moving paths, which increases the risks of collisions.

Luckily for us, fog lights have been around since around 1915. Why are they still a thing, though?

Fog Lights For Foggy Times: Are they necessary?

Fog lights are essential for driving in bad weather conditions because they can help you see and avoid obstacles that would otherwise be hard to detect. During nighttime or heavy rainstorms, your headlights can be easily washed out by the moisture; this means that you could lose track of your surroundings as you drive along. 

Typically mounted on a vehicle’s bumper, on the sides, or in the middle of a grille, normally at an angle of 45 degrees, their purpose is to assist drivers during poor weather conditions, including fog, sandstorms, storms, and any other situation in which visibility drops below 100 meters. With an additional spotlight and feature of wide illumination, the fog light takes the literal meaning – creating temporary visibility through thick weather conditions.

Such auxiliary car lights also help other drivers see you better at night—and can serve as an emergency light if necessary. If a car pulls out from behind you too fast—or is pulling out from far in front of you on the road with no median dividers—fog lights will let them know that there’s someone else on the road and give them a chance to adjust their speed and maneuvering accordingly.

Additionally, adverse weather, particularly fog, reduces depth perception, promotes low contrast (so objects may seem more dispersed), and fixate the vision on things at a closer distance. Their ability to cut through the fog like your grandma’s trusty bread knife, fog lamps offer can be of paramount importance to drivers, offering a greater sense of security in those tricky visibility situations. 

A sharp cutoff and minimal glare make these lamps perfect for illuminating the path ahead by creating a slender slice of illuminated road. They can also be helpful during snowy or rainy weather and for vehicles without high beam headlights.

Why should you turn your fog lights off when visibility improves?

Sure, it may seem like a good idea to set more than a shred of light at all times. Besides, your truck or SUV may look cooler. However, that is not a good idea. Why?

Constantly having the road surface lit up right in front of you may dilate your eyes , which, in turn, reduces your ability to see the darker road that lies beyond adequately. Moreover, from one side there’s the risk of fog blindness without fog lamps, but, from the other side, there’s the risk of tunnel vision in case fog lights are improperly used. In addition, on the road, having too much lights turned on is definitely distracting for other drivers, thereby increasing the chances of accidents.

In case visibility improves, not only do you see better with your headlights on, but the other traffic lads see better too and won’t be tempted to run into you. Is this some kind of weird coincidence? Or are there hidden conspiracies at work? No. The answer is simple physics: Fog lights project their light straight forward. Headlights, by contrast, project light in front of and behind you. This will give the poor visibility a bubble of light around you, making it easier for the other driver to see you, but not to be blinded by you.

In a nutshell, fog lamps can be a great addition to your car, but only in specific circumstances. Fundamentally, while fog lights can occasionally help you see further in front of your vehicle, they should be used sparingly, only in specific circumstances where their limited range indeed increases your visibility. Ultimately, turning your fog lights off is always more beneficial to you than turning them on under normal conditions.

If you’re looking for your next fog lights, remember that clear sight means clear decision-making. To help you find the right fog lights, we recommend checking out: