When is it appropriate to use your high beams?

Using high beams is appropriate on dark roads with no oncoming traffic because it maximizes your visibility and allows you to see further down the road, which is especially important in areas where street lighting is inadequate. High beams illuminate the road better than low beams, providing a broader view of your surroundings, which can be crucial for spotting obstacles, pedestrians, or animals that may cross your path.

In contrast, using high beams in heavy traffic conditions would be inappropriate as it can blind other drivers and create dangerous situations. Similarly, using high beams while driving in rainy conditions or when there is fog can cause glare and reduce visibility, as the light reflects off the water droplets or fog particles, making it harder to see. Hence, the best and safest scenario for using high beams is indeed when you are on dark roads and there is no oncoming traffic.