Sumuvalot

Sumuvalot, commonly referred to in English as fog lights, are a type of automotive lighting designed to improve visibility in conditions of reduced or diffuse visibility such as fog, heavy rain, snow, or dust. They are typically mounted low on a vehicle, often in the bumper or lower grille area, and emit a wide, low beam intended to illuminate the road surface just ahead without reflecting much light back from fog.

The beam pattern of sumuvalot is designed to stay close to the ground and sweep the area in front of the vehicle with minimal glare. This helps drivers see the edges of the road and potential obstacles while reducing backscatter that can occur with higher-mounted headlights in foggy conditions. Modern sumuvalot may use halogen, LED, or HID light sources, with LEDs becoming increasingly common due to efficiency and durability. In some vehicles the fog lights are wired to operate independently of the main headlights and may be activated in specific weather conditions or when driving at low speeds.

Usage and legality vary by region. Fog lights are intended for use in poor visibility and are typically not required in normal weather. In many jurisdictions, they must be turned off when high beams are in use, and some places restrict their use to certain times or conditions. Regular maintenance—keeping lenses clean and ensuring proper aim—is important for safe operation.

Sumuvalot differ from daytime running lights, which are active during daylight, and from headlights, which illuminate a broader area at higher light levels.