CDL General Knowledge TestDriving SafelyHard
A commercial driver is driving at night on an unlit rural road. They notice an oncoming vehicle's headlights. At what distance should the driver dim their high beams?
- AWhen the oncoming vehicle is approximately 1,000 feet away.
- BWhen the oncoming vehicle is approximately 100 feet away.
- CWhen the oncoming vehicle is approximately 500 feet away.
- DWhen the oncoming vehicle is approximately 200 feet away.
Show answer & explanationAnswer & explanation
Correct answer: C. When the oncoming vehicle is approximately 500 feet away.
Federal regulations and most state laws require commercial drivers to dim their high beams when an oncoming vehicle is within 500 feet. This prevents blinding the other driver and ensures safe passage.
Why the other options are wrong
- A. While earlier dimming is polite, 1,000 feet is not the legally required distance.
- B. 100 feet is far too close and would be dangerously late for dimming high beams.
- D. 200 feet is too close and could temporarily blind the oncoming driver.
Headlight Dimming Distance (Oncoming)
The legally mandated distance at which a driver must switch from high beams to low beams when approaching an oncoming vehicle to prevent glare and maintain visibility for other drivers.
- Required at approximately 500 feet for oncoming vehicles.
- Prevents temporary blindness (glare) for other drivers.
- A crucial aspect of safe night driving.
Memory trick: Five hundred feet, dim your brights, make the night safe and right!