Fog lights

What are Fog Lights and When Should You Use Them?

by Zutobi · Updated Jun 30, 2022

Driving in unsafe weather conditions can make driving extremely challenging. Luckily, car makers have implemented features to help drivers navigate situations such as these. UK law dictates that fog lights must be included in the rear lights, while front fog lights are an added extra. Despite their importance, many drivers confuse fog lamps for high beams or other similarly coloured lights.

Car enthusiasts will tell you that fog lights are a must-have, especially in cold and rainy climates like in the UK. However, a tool is only as good as how it’s utilised. In this article, we’ll teach you everything you need to know about fog lights and when they should be used.

What are Fog Lights?

Fog lights are featured on the front and/or rear of vehicles and are used to increase driver visibility in fog. They are generally positioned under the main headlights and are shaped like a bar. The location in which fog lights are located on the vehicle allows them to emit light that pierces the fog and creates a clear field of vision for the driver. As its name suggests, this is a serious lifeline in foggy conditions, where visibility is extremely low and normal headlights can’t pierce through very well.

Fog lights come in both yellow and white, depending on the specific car’s manufacturer.

This is the dashboard icon for front fog lights.

Difference Between Fog Lights and Normal Headlights

Fog lights and main beam lights are completely separate and each features its own assembly. You’ll find headlights on every single vehicle on the road, while front fog lights are only offered as an upgrade in many car models. When a car is turned on, the main beam headlights are generally the first to turn on. Fog lights need to be manually activated before they begin working.

  • Main beam lights lie in the front center of the vehicle on either side of the vehicle grill. They usually have a rounded shape, but are also square shaped on many vehicles.
  • Fog lights sit just below the beam lights and are long and rectangular.

Using Fog Lights

It is important for drivers to understand the type of situations in which they can use fog lamps, and when they should not be used.

In the United Kingdom, fog lights should be used when visibility is severely restricted such as in heavy rain, fog, or snow. However, the Highway Code also states that you must switch your fog lights off as soon as visibility improves, meaning they are only to be used temporarily. The reason being that they are very bright and will blind other drivers if left on.

How to Use Fog Lights

Front Fog Lights

Your front fog lights are usually activated via a separate switch from the main light control. Some cars also allow drivers to utilise fog lights from a button in their infotainment cluster. There are a multitude of ways to turn on your fog lights, so it’s best to consult your owner’s manual for more detailed information.

Rear Fog Lights

Rear fog lights are bright lights that are generally the same brightness as your brake lights. They are, as previously mentioned, mandatory on all new vehicles in the United Kingdom. Rear fog lights are used so vehicles behind you are able to see your vehicle even in poor visibility situations.

When to Use Fog Lights

You can use fog lights in a variety of low visibility settings, this includes fog, heavy rain, and storms. Using low or high beam lights in these situations can make visibility worse, as their positioning makes light reflect back towards the driver, this is especially true when it comes to high beam headlights (never use high beams when driving in fog!).

The low placement of fog lights allow them to emit rays that cover surface area below the fog, allowing you to clearly see what obstacles or other vehicles exist in front of you.

Can You Use Fog Lights When There’s No Fog?

Technically speaking, you can use your fog lights whenever you’re in an area of low driving visibility or poor weather. However, keep in mind that fog lights are not designed for driving at high speeds and must be turned off as soon as visibility improves.

Are They Good to Have?

The answer is yes! If you have the option and can afford the upgrade, fog lights are an essential feature that will allow you to get a better view of the road. As we live in a country where weather can be unpredictable, purchasing a vehicle with front fog lights will allow you to drive your vehicle at any time without fear of reduced visibility.

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