DRLs Considered Harmful

Dispelling Some Myths

First of all and contrary to popular belief DRLs are not mandated by law in the United States. DRLs are permitted by the National Highway Traffic Safety Administration (NHTSA) decision in 1992. This federal mandate necessarily overthrows laws in a majority of the US states (including my home state of Texas) which prohibit the use of headlights during clear daylight hours.

Now why would anyone in their right mind want to disable one of their car's saftey features? The fact of the matter is that DRLs have not been established in the US as a safety feature. Please see the Drivers Agains Daytime Running Lights' (DADRL) studies page for in-depth information.

DRLs Good

So what is the case for DRLs? Lights on during the day do, in fact, make one's car more visible to other motorists especially in alternating shadow and full sunlight situations. Scandanavian countries and Canada where lighting conditions are quite different than more southerly latitudes like the US were first to implement and, in many cases, mandate DRLs.

DRLs Bad

The extra visibility given by DRLs unfortunately occurs at the expense of vehicles which do not have them. Other vehicles become obscured by the glare from DRLs making them less visible. Safe visibility can only be had when all cars are as similar as they can be. Everyone has DRLs — all cars must be retrofitted — or no one has DRLs.

Then we have the case of the motorcycle. Motorcycles in the US have had DRLs for a long time to increase their visibility. There is a good reason for this. Ask any motorcycle rider you like how many times a car or truck has pulled out in front of or changed lanes into them like they weren't even there. Drivers in the US seem to have a blind spot when it comes to motorcycles and there are many campaigns to increase motorcycle awareness. "But other drivers pull out in front of my car all the time!" Your car offers significantly more visibility and impact protection than a motorcycle. Their visibility is significantly more important than that of a car. Already I regularly see motorcylces driving around with their full-intensity high-beams on to better be seen in the wash of automobile DRLs.

There are several excellent sites listing the reasons people are against DRLs and I see no reason to recreate that effort here. Please visit Drivers Against Daytime Running Lights [www.lightsout.org] and Pros and Cons of Daytime Running Lights. The following list summarizes some of my own comments beyond their well-reasoned arguments.

1. DRLs annoy other drivers. DRL proponents often fall back on the lame "just get over it" assertion. An equally reasonable and considered response might be, "F*** you," but neither advances the argument. It is a fact of human nature that people tend to avoid disturbing stimuli. You cannot control what disturbs other drivers but you can stop disturbing them.
2. DRLs decrease visibility of critical traffic signaling methods by removing the ability to turn off headlights and obscuring turn signals.
3. You do not have control to turn off DRLs when you should. In addition to those mentioned at other sites, further examples of everyday situations where headlights should be turned off are when
   1. driving up to a parking space that faces into a bar, restaurant or shop with large windows. Pointing your blazing headlights at patrons inside is patently rude. You are certain to be known as "that jackass" upon entering. Congratulations, jackass!
   2. parked waiting for passengers, retrieving mail, reading a map, etc. Reducing glare from your headlights allows pedestrians to be seen. Vehicles with their lights on are assumed to be moving so, just like using turn signals properly, please communicate your intent not to move to other drivers. (Then turn on your headlights and use your turn signals when pulling out.)
4. DRLs appear to cause many drivers forget when they should engage their real headlights. DRLs only illuminate forward-facing lights which is dangerous at night, in fog and other low light conditions. Don't these people ever look at their dashboard instruments?
5. DRLs decrease bulb life. This is a fact. The lower voltage of DRL operation does not prevent it. When one bulb is burned out it is significantly more likely that a vehicle can be left with no headlights at all if the other bulb burns out. This is a very dangerous situation at night.
6. DRLs decrease gas mileage slightly. True, the decrease is measurable but better solutions for saving fuel abound.

Again, please see those sites linked above for a complete, well-written argument that is not duplicated here.

I do not wholly believe DRLs are simply a vehicle (pun intended) to sell light bulbs and new car/retrofit electronics. Companies like GM, Volvo, Volkswagen and Toyota are marketing safety to sell product. The cynic in me says what is important here is the perception of safety to ignorant consumers rather than actual safety. Were actual safety the issue then cars would have roll cages, 4-, 5- or 6-point harnesses and occupants would wear helmets and protective clothing. Unfortunately in our society automobiles are considered fashion accessories and such safety measures would be bitterly opposed.

So What Is the Answer?

The answer is the same as it always was: driver education. Drivers need to turn on their low-beam headlights in low ambient light conditions and not in the daylight under clear skies.

Do not drive with only your parking lights or your fog lights illuminated. (Hmmm…something about those words, "parking, fog.") They do not provide the proper lighting for visibility even at dusk and driving this way is illegal in most states though not well-enforced. There are a few conditions in which this is appropriate (e.g. military bases, astronomical gatherings, etc.) and in all of them you're moving at less than 20 mph and not on public roads.

When to Turn On Your Headlights

A good rule of thumb is if you need to turn on your windshield wipers you should also turn on your headlights. Obviously this is only a good starting place but not enough. Some examples:

• fog — You are invisible to other drivers in the fog. Turn on your low-beams only as the high-beams will only reflect back into your eyes. The same is true of driving lights. The same is true of early DRLs on the high-beams. DRLs only illuminate front lights leaving you invisible from behind. Fog lights are designed to throw a short but wide pattern and should be used in conjunction with low-beams. They are only useful in very thick fog in which one must drive very slowly otherwise you are simply overdriving your fog lights. By "overdriving" I mean that by the time you see something in your light pattern you don't have enough time to react before you collide with it. Fog light tip: they don't look cool.
• rain, mist — This is covered by the rule above. Light doesn't travel as well through the water in the air (or on someone's windshield) and rain is typically accompanied by cloud cover combining to lower ambient light. Silver and gray cars are especially hard to see in inclimate weather.
• dusk, dawn — During the transition from night to day your headlights transition from being a device to help you see to one that helps you be seen. Please turn your lights on as the sun nears the horizon in the evening and in the morning leave them on until it has risen somewhat in the sky. Additionally some cars are driving facing into the sun and need all the visual clues they can get. Your headlights help separate you from the landscape and the scrapheap.
• parking garages — Often parking garages are dim and a driver's eyes can become momentarily blinded as they pass outside areas brightly lighted from outside. Parking garages are filled with safely unmoving cars which can be hard to discern from dangerous moving cars. Do yourself a favor and turn on your low-beams to make yourself more visible. Again, DRLs only illuminate front lights so turn on your headlights to illuminate your tail lights so you can be seen from behind. Again, parking lights are for parked vehicles, not moving vehicles.
• night — I've seen this often enough to bear mentioning. Please try not to be brazenly stupid. If not you will likely be given the opportunity to prove your sobriety to an individual who will not appreciate the joke.

Links

• Drivers Against Daytime Running Lights (DADRL)
• National Motorists Association DRL page
• National Highway Traffic Safety Administration (NHTSA)
• Pros and Cons of Daytime Running Lights

Comments

If you would like to contact me regarding the content of this page please feel free to do so. Likewise I will feel free to use your comments in any way I see fit including my freedom to ignore them entirely. If you are in favor of DRLs please send your comments to drls+good AT wolfeden DOT org. If you are against DRLs please send your comments to drls+bad AT wolfeden DOT org. Thank you for reading.