Philadelphia Drivers License Practice Test

In foggy conditions, which headlight setting should you use?

1. High beam

2. Low beam

3. Both high and low beam

4. Fog lights only

The correct answer is: Low beam

In foggy conditions, using low beam headlights is the recommended practice. Low beams provide adequate visibility while reducing glare, which is critical in fog as high beams can reflect off the moisture in the air and create a blinding effect, impairing your ability to see. This glare can make it harder for both the driver and other road users to navigate safely. Using low beam headlights ensures that the light is cast downward onto the road surface, allowing for better visibility of the immediate area and road ahead without causing excessive brightness that can bounce back at you during foggy conditions. This choice helps maintain safety for all drivers on the road. While fog lights can also enhance visibility in fog, they are typically used in conjunction with low beams. Fog lights are designed to light the road immediately in front of the car with a wide, low beam that minimizes the amount of light that is directed upward, further reducing glare. However, low beams alone are the essential setting to use when driving in fog.