For Device Driver Download and Updates Click Here >>

Daytime running lights: a warning

By: Dan Keegan

Date: Wednesday, 20. January 2010

As more cars use daytime running lights, the risk to drivers not using them will steadily increase, according to Transport Canada studies. Starting with the 1990 model-year, all cars sold in Canada must have Daytime Running Lights (DRLs).

The effectiveness of daytime lights in reducing accidents has been proven by research in a number of countries, including Canada, the USA, Finland, and Sweden. The systems have been shown to reduce multiple vehicle collisions by as much as 32 per cent. Finland was the first to make their use mandatory in 1972. Sweden followed suit in 1977.

But Transport Canada's research into the use of daytime lights showed another effect, one that will become more important as daytime running lights become a standard part of the driving scene. Drivers who don't have daytime running lights run a risk of being "masked" by drivers who do. Research carried out for Transport Canada in the mid-'70s by Dr. Dennis Atwood, showed that drivers meeting a line of cars in a passing situation were more likely to miss an oncoming car without headlights if it were surrounded by cars that had headlights on.

Atwood's results played a large part in the change in Ontario's traffic laws requiring automobile headlights to be switched on one hour earlier in the evening and switched off one hour later in the morning.

The masking effect, which Atwood attributed to either the glare or the distraction effect of the headlights (or a combination of both) was strongest at dawn and dusk and increase rapidly as the level of light dropped off. At sunset, the light level can drop by a factor of 10 in as little as 10 minutes, he says, and the risk increases rapidly for drivers not switching on their headlights.

Atwood believes that as a greater proportion of drivers begin using daytime running lights, the danger of masking will increase for those left without them.

Daytime running light systems have a lower intensity than low beam headlights and last longer with less energy use.

While the biggest advantage of the systems is when natural light is low, such as at dusk or dawn or when skies are overcast, research indicates that they are also an advantage even on bright, sunny days. Because the human eye is light-seeking, drivers will see an oncoming car sooner and make a more accurate estimate of its rate of approach.

The effect is particularly important for peripheral vision, which may not see an object at all unless it contrasts sharply with its background or moves against it. Using daytime lights significantly reduces the chances of a car, cyclist or pedestrian moving unexpectedly into your path.

Atwood suggests that drivers of cars that don't have daytime running lights as a standard feature purchase a retrofit kit rather than using low beams.

Further comments to this article have been disabled.

All Comments (10)

Showing 1 - 10 comments

E Quarry,

I have a new car which has daytime running lights but am finding it very dangeous at nighttime because I keep forgetting to put on my main lights because I see my dashboard lit up and because have front lights on totally forgetting my main lights are not on and of course is no rear lights with these new daytime lights, grrr any ideas on work around?

Ruben Johnson,

Please visit the u tube link below to see some highway safety improvements for fleets that operate and repair the roads systems across north america

Ruben Johnson,

The Insight electronics version of the DRL
uses the low beam at half wattage and does not offend uncoming traffic and will not blind us in the rear view mirrors by vehicles following us, and when you turn on the head lamps there is a automatic overide of voltage when low beam is selected, we have had 4 vehicles with this system and love the results

Ruben Johnson,

We have DRL in Canada for years and its a great way of being able to see oncoming cars when their color blends with pavement or weather conditions, The Kit that we favor does not require extra lights and operate in the low beam circuit when the engine is started, there have been countless accident prevented with the installations GO for it, adding extra lamps that are lit at night is not a good option


does running day light kill the bulbs life expand?

hammond deggs,

As a retired trucker I found that cars without drl were hidden in the tire spray and you had no way of telling when to pull right without hitting them. now people disconnect them without a fine. what fools.


No Mike. Daytime Running Lights are specially designed for this use. If you understand how peripheral vision works you will understand that they don't need to be very bright.

If some car manufacturers are not doing it right then they should run into problems with regulators.

- and high beams are NOT intended ot be irritating. If they are, then they are either not used properly or are wrongly aimed.

Mike W,

They are daytime high beams, with reduced voltage, not daytime running lights. Running lights are running lights, day or night.

Nearly all of the studies I've seen are by parties with a vested interest, say GM in the US, which would rather put irritating lights on a car and call it in the interest of safety, than say put good brakes on a car. It's cheaper.

Low beams just look dumb during the day, high beams are intended to be irritating to other drivers. Which kind of says something about manufacturers who promote them...



Daytime running lights were originally developed for northern countries which often have dull, cloudy and rainy days even in summer time.

However, most Canadians live way farther south than that. For example Toronto is not much farther north than the northern border of California.

All canadian cars now have special Daytime running lights (DRLs) but i've NEVER heard any canadian driver complain about being "blinded" by these lights. They're not that bright, and they use very little energy.

Another very important thing, as the article above notes, is that DRLs make it easier to see a car in peripheral vision, i.e. out of the corner of your eye. That's important.

DRL is evil,

If it is why it is not mandatory in USA anymore? Does USA more stupid than Canadians? I doubt.
which exactly? Finland and Sweden should not be considered at all because they in North.
It is pretty stupid to drive with DRL during sunny days. Many times was blind by trucks behind me during sunny day...
Bad thing that many drivers forgot to turn on back light in the night, because in front of them a lot of lights from their DRL. That is dangerous. Not to say that lamps burned out more often not to say of expressive fuel consumption.

Truck Driving Jobs

driving information
other driver info
travel information for drivers

Travel and Driving