Bright high beams can dazzle the drivers around you, so dim them within 500 feet of an approaching vehicle and when following another vehicle within 500 feet. In fog, rain or snow, low beams also work better because high beams bounce back off the moisture.
High beams light the road much farther ahead, so use them whenever it is safe and legal. Dim them when traffic is coming toward you or when you are close behind another vehicle.
If you need more distance to stop than you can see ahead, anything that appears at the edge of your vision will already be too close to avoid. When a vehicle approaches, look toward the right side of the road instead of at its lights, and remember that low beams show you less of the road, which calls for a slower speed, not a faster one.
Your speed should always let you stop inside the stretch of road you can actually see. When low beams reveal about 250 feet, your stopping distance must not go beyond 250 feet, and rain or fog may call for an even slower speed.
Low beams light a shorter stretch of road than high beams, so slow down until you could stop inside the area your lights reveal. Going faster than that means overdriving your headlights, and a hazard could appear too late for you to stop.
Low beams do not reach nearly as far down the road as high beams, so slow down enough that you can stop within the distance you are able to see.
Your headlights reach only so far, and if your speed needs more room than that to stop, something that suddenly appears in the beams may be impossible to avoid. Staring into oncoming lights can leave you briefly blinded, and a bright instrument panel makes it harder to see outside, so keep the dash lights turned low.
Staring into bright headlights can blind you for a few seconds, which is long enough to lose track of the road. Shift your gaze to the right edge of your lane to hold your position while you watch the other vehicle out of the corner of your eye, then look ahead normally once it has passed.
Relying on low beams all the time is a common error that sharply limits how far ahead you can see. Switch to high beams whenever the law and conditions allow, and dim them for nearby traffic and in fog, rain or snow.
With low beams you can see only about 250 feet ahead, much less than with high beams. Reduce your speed so that you could still stop your vehicle inside the stretch of road your lights reveal.
Low beams light only about 250 feet of road ahead, so dimming your headlights shortens how far you can see. Slow down enough that you can stop within the distance your lights reveal.
High beams let you see much farther down a dark road, so use them when conditions and the law permit. Lower them well before you get close to other traffic, such as when an approaching vehicle is within 500 feet, and never answer another driver's glare with your own high beams.
The best way to deal with dense fog is to avoid driving in it, so get off the road at a rest area or truck stop and wait until you can see well again. Fog does not reliably thin out once you are in it, taillights ahead may belong to a vehicle that has already left the road, and a vehicle stopped in a travel lane is likely to be hit from behind.
Fog is made of tiny water droplets that throw the strong light of high beams back at you as glare, so you actually see less. Low beams and fog lights are aimed lower and cause less glare, and using them even in daytime also helps other drivers notice your vehicle.
Every question in this set has its own page with the correct answer and an explanation.
