We all know that headlights must be turned on at night – after all, you can’t exactly be a safe driver if you can’t see anything.
However, you may have come across some laws or signs that may have confused you. For example, in certain mountain roads in California, you might see signs that indicate “D
aylight Headlights Required Next XX Miles” or something similar. Additionally, you may have even seen the newest automobiles equipped with Daytime Running Lights – or DRLs for short. What’s the deal here?
Daytime Headlight Use – The Obvious Reasons
First off, there are a few circumstances in which daytime headlight use is not only strongly recommended, but can even be required by law. The primary reason is inclement weather – rain, sleet, snow, hail, or fog are good reasons to use your headlights.
In some states, such as Alabama and California, you’re actually legally required to have your headlights turned on when your wipers are on. After all, if your wipers are on, weather’s likely terrible – and if weather’s terrible, so is visibility. Be sure to check your local headlight laws to see if this applies to your state.
Daytime Headlight Use – The Not-So-Obvious Reasons
When it comes to the aforementioned “Daylight Headlights Section,” however, the reasons aren’t so clear – but it’s the same train of thought. In these sections of road, visibility is usually difficult and can be limited. Having your headlights on during these periods can make it infinitely easier to spot oncoming traffic and any other cars around you.
This is why daylight headlight sections of road are often found in mountainous areas, often on two-lane highways where each lane travels opposite ways. Narrow lanes can often lead to reduced visibility, which can be a dangerous situation for heavily traveled mountain roads. Even though it’s the daytime, headlights are still easily visible by other drivers, and can hopefully be seen to prevent potential of a collision.
What About Daytime Running Lights?
DRLs follow the same mentality – even in the day, a car with headlights on is easier to spot than one with no headlights. It’s another precautionary measure on some newer vehicles to reduce the risks of collision.
Most studies done around the world have concluded that daytime running lights can decrease collisions by anywhere from 5 to 10 percent. This data is convincing enough that, in many countries, all automobiles sold are legally required to have DRLs installed. Canada, Norway, and Sweden are some of the many countries who abide by this law.
Ultimately, while the effects of daytime lights on driver safety and collision rates may not be ironclad, there’s no drawback to using headlights during the day. It’s a classic “why not?” scenario: if it has the potential to reduce collisions and improve driver safety, with no real drawbacks or negatives, then why not have them on at all times?