Fog lights are used to illuminate a motor vehicle in particularly poor visibility conditions due to, for example, fog, rain, or snow. They are mounted below the headlights. With equipment features such as a parking heater, fog lights are useful equipment in autumn and winter. They are typically located slightly below the main headlights. The fog light is mounted low on vehicles to provide additional lighting in poor weather conditions.
In the UK, front fog lights are optional, while a rear fog light is mandatory. Since 2011, daytime running lights (DRLs) have been mandatory on new cars. LED fog lights can be used as daytime running lights, provided they have an appropriate dimming function and are mounted symmetrically at the front of the vehicle.
WHEN SHOULD YOU USE YOUR FOG LIGHTS
It is mandatory to use headlights when visibility is severely reduced, for example, when you cannot see more than 328 feet ahead. You are also allowed to use fog lights, but you must turn them off when visibility improves. Using them with dipped beam headlights makes little sense, as broader lighting is only achieved at short distances. The dangerous glare for the driver, caused by dense fog, is not minimized with this lighting combination. This glare can occur in foggy conditions, for instance. The fine water droplets reflect the light that hits them and can dazzle the driver. In this case, dipped beam headlights create too much scattered light at the driver’s eye level. Fog lights, on the other hand, illuminate the area below their mounting height and thus avoid glare.
Do not turn them on unless you have to; the UK Highway Code states that you must not use them unless there is a significant reduction in visibility.
HOW TO TURN THEM ON
On some cars, the buttons are located on the side of the steering wheel, while on others, they are on the turn signal lever, which needs to be turned to switch them on. There may be slight variations depending on the make and model of your car, so be sure to refer to the owner’s manual for specific instructions.
REAR FOG LIGHTS
In the UK, these must be mounted in the center or at the rear of the vehicle. A rear fog light is a focused light and must be installed perpendicular to the rear of the car. They can make it easier to detect a vehicle in front of you when driving in foggy conditions. Do not be tempted to use other cars’ lights as a reference, as they may give you a false sense of security.
ARE YELLOW FOG LIGHTS LEGAL IN THE UK
White and yellow are permitted in the UK. Yellow lights have their advantages, especially during the winter months when you might have visibility issues due to the weather. Dark yellow is less dazzling than white, as it has a cooler Kelvin temperature and a higher wavelength than white light. Longer wavelengths can improve visibility since the light is more refracted and thus travels further, but they do not necessarily enhance visibility. They reflect fewer water particles and therefore do not dazzle you as much, nor oncoming traffic.