Safe driving and emergencies
You must drive through heavy fog. Which lights should you use?
- Low-beam headlights. Correct answer
- High-beam headlights, to see farther.
- Parking lights or fog lights only, to reduce glare.
Why
In fog or heavy smoke, high beams do the opposite of what you want: the light reflects back off the droplets and creates glare in front of you. Use your low beams. Driving with only parking lights or fog lights is never allowed. Better still, the handbook suggests postponing the trip until the fog clears. If you must drive: go slowly, make sure you can stop within the distance you can see, increase your following distance, use your wipers and defroster, avoid changing lanes or passing unless absolutely necessary, and listen for traffic you cannot see. If it gets too thick to drive safely, pull off the road, turn on your emergency flashers and wait.
Where this comes from
California Driver's Handbook, June 2025 edition. The correct answer is Low-beam headlights.
The rule behind this one
Safe driving and emergencies in California goes through the whole topic, with the page of the California Driver's Handbook behind every rule.
More on safe driving and emergencies
- A child is under 2 years old, weighs less than 40 pounds, and is shorter than 3 feet 4 inches. How must the child ride in your vehicle?
- A front tire blows out while you are driving at highway speed. What should you do?
- You are 17 and hold a provisional license. When may you use a cell phone while driving?
- You have to run into a shop for a few minutes. Under what condition may you leave your five-year-old in the car?