NC CDL General Knowledge Practice Test

Using low beam headlights is the safest lighting option when driving in fog. Fog creates a low-visibility environment, and high beam headlights can actually make visibility worse because the light reflects off the fog particles, creating a glare that can obscure your vision. Low beams are designed to illuminate the road directly in front of the vehicle and are positioned to minimize the reflection off atmospheric moisture, therefore providing optimal visibility without causing excessive glare. Daytime running lights, while they increase your vehicle's visibility to other drivers, do not adequately illuminate the road ahead in low-light conditions like fog. They do not provide the same level of illumination as low beam headlights. Driving without lights at all is unsafe, as it severely limits your ability to see and be seen in foggy conditions. Therefore, using low beam headlights is essential for safe navigation through fog.