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When Should You Use High Beam Headlights?

Lost Hwy 52 by Wayne Wilkinson

How Well Can You See Ahead?

Many users are confused about when to use of low beam and high beam headlights.

Think about this: low beams let you see about 200 feet ahead. It can take about 200 feet to stop when you drive at 30 mph. That is almost half a city block in length. If you cannot see 200 feet ahead, you may not be driving safely at 30 mph. By the time you see an object in your path, it may be too late to stop without hitting it.

Headlights on “upper” or “high” beam let you see about 350-400 feet ahead. 400 feet is your approximately stopping distance when driving at 50-55 mph. That is about the length of a city block.

In other words, high beams let you see twice as far as low beams.

When to Use High Beam Headlights

In any situation when you cannot see well enough ahead, you should start by slowing down. Remember the basic speed law and the two-second rule. When you cannot see well enough, you must increase your following distance which means more seconds. If there are no oncoming vehicles, turn on your high beam headlights.

In general, you should always use high beams outside cities and in rural areas, as long as there are no other vehicles around. Dim your lights when there are oncoming vehicles, or when you are approaching another vehicle from behind.

During poor visibility it is particularly important to use high beams on unfamiliar roads, on dark city streets, in construction areas, or where there may be people or bicyclists along the side of the road. Remember to adjust you speed and not overdrive your headlights.

You must also dim your headlights in all situations when there is a risk of blinding other drivers with your high beams.

Exception from the Rule

Sometimes, however, high beams will not improve your visibility. In fact, it will do the opposite.

This happens in fog, heavy rain, and snow. In these situations, the light from your high beams will reflect back from the fog/rain/snow and cause glare. The glare will make it more difficult to see ahead. To improve visibility, switch to low beams.

Some vehicles have fog lamps that may be used in combination with low beams. Fog lamps will illuminate road edges and pavement markings, making it easier to stay in lane. The should only be used in heavy fog, rain, or snow. Turned them off during normal driving conditions.

The Use of Low Beam Headlights

There are several situations when it is better to use low beam headlights. It is also required by law to dim high beam headlights when you meet a vehicle approaching from the opposite direction or when you approach another driver from behind. [Read more …]

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  1. In a coach bus what is the folllwing distance on a clear night?

  2. Isn’t there a rule of thumb about driving with high beams and large distances between your lane and the oncoming vehicles across a large medium between you?

    • Provinces in Canada can have a rule that says that you don’t need to dim your headlights for oncoming traffic if you are driving on a divided highway where the distance between the roadways is 70 ft. or more. State laws in U.S. don’t address divided highways. You must dim your headlights every time there are oncoming vehicles.

  3. this information has helped me immensely as my son has been killed in an accident while being knocked down on a dark road

  4. so are you answering me question High or low in a fog?

    • In general, you should use low beam headlights in fog. The reason for not using high beam headlights is that high beams may reflect back from a thick fog and cause glare. The fog acts like a mirror and you will see a strong light from your own headlights. This glare often cause discomfort and reduce visibility by making it harder to see the road ahead.

      Low beam headlights will cause less glare, and you will see the road better. In some situations, there is a trade-off between visibility and glare depending on how thick the fog is.

      If your vehicle has front fog lights, these lights are directed towards the road surface and may be used in fog, rain, or snow. They will help you see pavement markings and stay in lane. As soon as the fog clears or visibility improves, these fog lights must be turned off.

      Remember, if the thick gets too thick, it is always safer to find a place to pull off the road.

  5. I think I should use high beam when it’s late at night in a suburban-rural area. Especially when you get off a loop exit

  6. Why do so many people now use their high beams while driving on inner city streets ? I though it was illegal. Definitely dangerous, thoughtless and dumb !

    • Kate with cut downs on law enforcement and reduction in road traffic police rule of jungle prevails. Even when someone is caught in the act chances are the case will be dropped for lack of evidence -as the dasboard camera of the accused will show him somewhere else at the alleged time if offence

  7. Perfect practice

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