Tennessee Permit Practice Test

When is it safe to drive in fog?

1. When visibility is clear and you can see at least 500 feet ahead

2. When using high beams

3. When fog lights are on

4. Driving is never safe in fog

The correct answer is: When visibility is clear and you can see at least 500 feet ahead

Driving in fog conditions is particularly challenging due to reduced visibility, which can impair a driver's ability to see other vehicles, traffic signals, and road signs. It is considered safe to drive in fog when visibility is clear and you can see at least 500 feet ahead. This level of visibility allows for adequate stopping distance and the ability to react to sudden changes in the driving environment. When visibility is restricted, driving can become dangerous, as other vehicles may suddenly appear in your path, or you may not see road hazards in time to avoid them. High beam headlights tend to create a glare effect in fog, which can further reduce visibility instead of improving it. Fog lights are specifically designed to illuminate the road directly in front of a vehicle without creating excessive glare, but they are more effective at very low visibility levels. Thus, the ability to see clearly at least 500 feet ahead is crucial for safe driving in fog conditions, making this answer the most appropriate in ensuring a driver can navigate safely.