The Eight Most Important Things to Know About Fog Lights

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It’s easy to find yourself driving down the road with a clear view, only to get stuck in a thick cloud of rolling fog minutes later. For many drivers, fog is a serious challenge since few have a lot of experience driving in it. Visibility is always a challenge, especially at night or in low-light conditions.

That is why most cars come with some kind of fog light setup in addition to the regular headlights. Designed to cut through fog more effectively than headlights, fog lights can actually be a lifesaver in dangerous driving conditions. 

It’s important to know how to use fog lights correctly, however, to stay safe when visibility is poor. So, here are eight things to know about fog lights to stay safe in foggy driving conditions.

Some headlights at night
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Fog lights point down to illuminate more of the road than headlights

How Fog Lights Work

Don’t get fog lights mixed up with regular headlights. The point of fog lights is to shine where headlights aren’t effective. In foggy conditions, headlights end up illuminating more fog than anything else. This is partly due to the beam of the headlights that covers a lot of surface area, especially directly in front of the vehicle. 

Halogen, HID, and LED fog lights use a different design that is better suited for foggy conditions. The beam they cast tends to angle down, covering more of the street than things directly in front of the car. 

Most fog lights also have a yellowish hue that can penetrate deeper into fog than common headlight colors like blue or white. This is somewhat debated in scientific circles, but many fog light manufacturers stick to this convention. The different designs mean you will get the best results using each light in the right conditions.

When to Use Fog Lights

This one seems obvious right off the bat. Fog lights are for fog, right? Yes! You do get the best results when you actually use the fog lights in foggy conditions. The problem, however, is that people tend to overuse them, even when it’s not foggy outside.

Some drivers, for example, have the habit of using fog lights at night for extra illumination. While this does light up the road more, it’s usually unnecessary if the headlights are aimed correctly. As a result, this just wastes the energy and bulbs, reducing the light’s lifespan.

You Can Add More Lights (Especially for Off-Roading)

Don’t have any fog lights on your vehicle? Need more for challenging off-roading conditions? The great thing about fog lights is aftermarket and OEM fog light kits are common and relatively easy to mount.

Many popular off-roading manufacturers, like Toyota and Jeep, purposely design their off-roaders to accept different fog light assemblies and kits. In fact, whenever you see a truck or SUV meant for off-roading coming down the street, you will likely see a whole array of LED headlights and light bars attached for different weather conditions. 

The good news is you don’t need the whole off-road setup to add a fog light or two. The key is finding a good mounting spot on your vehicle and the right type/size of fog light. Check out different bulb options, like LED light bulbs or halogen fog lights.

Below or above the bumper tends to be the best mounting spot. If you don’t have any space, you can look at some bracket options that attach to the frame of the car. The lights will wire directly to the car’s power supply.

You Need to Choose the Right Color

There are often some intense debates over the best color for fog lights. A good majority of manufacturers stick with “selective yellow” that theoretically has longer wavelengths needed to penetrate deeper into a wall of fog. This is why you will see many fog light products with a yellow hue, especially with halogen bulbs and led bulbs. 

Others disagree, however, that yellow really makes a big difference, particularly if the light itself doesn’t have the best construction quality. Some drivers prefer white lights. At the very least, remember that color alone won’t make a good fog light. The design and construction need to be high in quality to get good results. 

There’s a Right Mounting Spot

Most fog light bulbs mount low on a vehicle, much lower than normal headlights. This makes it easier to illuminate the road directly without casting direct light into the fog itself. Better still, a lower angle compliments the headlights so you don’t have unnecessary overlap between your normal-use and fog-specific lights. 

Keeping the lights under a foot from the ground is a good rule of thumb when figuring out just how low to go. If you have space around your bumper (above or below), this is a good starting point. You can also check out aftermarket mounting solutions like brackets and front grille guards if the bumper doesn’t have the room.

There’s a Perfect Angle for Fog Lights

If you are installing your own fog lights, you will need to get them aimed correctly before using them. Beyond the design and position of the lights, the illumination angle will determine how much of the light output hits the road versus the fog in front. You can’t have them straight ahead since too much light will escape, but a low angle will only light up the immediate area in front of the bumper.

A guide can help get the right alignment for the beam of light. If you can find a flat stretch of road or driveway that meets a 90-degree wall, you can park the vehicle 25 feet away and move the lights around. The perpendicular surfaces will let you see how much light is cast downward versus straight out to get the best illumination. 

Fog Lights Don’t Play Well with Brights

You can use other lights in addition to the fog lamps while driving in poor visibility conditions. Using your regular driving lights, for example, maybe necessary if you are driving in light fog at night. Other indicator lights like rear lights, turn signals, and flashers also make you more visible to other drivers.

The one light to avoid with fog lights is your high beams. Since the brights point straight ahead, they will cast out more light into the fog than the street itself. The results are often worse than just driving in fog with headlights alone.

You Shouldn’t Rely Solely on Them

Finally, as with anything else, fog lights aren’t the only thing that will keep you safe in foggy conditions. Safe driving is equally important, meaning you’ll need to change your driving to match the challenging conditions. In other words, you can’t drive like normal in fog, even with the right lighting setup.

More than anything else, slow down while driving in fog. Slower speeds increase your reaction time to things you may not be able to see through the fog until it’s too late. If possible, leave extra following distance between yourself and other cars. Keep yourself visible with flashers or hazard lights. In a worst-case scenario, pull over and wait for the fog to lighten up.