Researchers from the Netherland’s “Utrecht University” and France’s “Université Bordeaux II” compared the effects of driving under the influence of alcohol and hours of driving on the highway at night. Surprisingly, the results of the experimental study showed that the driver’s driving ability, who drove in the dark, diminished quickly over a number of hours, to the level of a driver who drives under the influence of alcohol.
The International team was headed by psychopharmacologist Joris Verster, PhD from Utrecht University.
The reseach subjects in the study were fourteen (14) men, between the ages of twenty-one (21) and twenty-five (25).
These young men drove on a public highway, uninterrupted at night for two (2) hours (3 a.m – 5 a.m), four (4) hours (1 a.m – 5 a.m) and eight (8) hours.
They drove at a constant and consistent speed of 80 mph, while staying centered in the lane in which their vehicle was travelling in.
Their driving performance was monitored and recorded and any deviations (the weaving of the motor vehicle driven) from the center line was measured over time by the researchers.
The researcher found the following:
When fatigue began to set in, in an attempt to combat tiredness, the driver would turn up the music on the radio and/or roll down the vehicle’s window for some fresh/cold air and neither action seemed to make any measurable difference in the driver’s performance.
Reseach team head Joris Verster said of the study: “I hope this study gives drivers more awareness of the risk of prolonged driving. After two continuous hours of driving at night you should really take a break.”
The Journal of Sleep Research published an article on this research called Prolonged nocturnal driving can be as dangerous as severe alcohol-impaired driving
General Motors is looking at creating enhanced vision systems which would make night driving and driving in fog and related conditions, safer (see YouTube video). Here are some helpful tips from General Motors’ educational series website, (under Teen Driving):
Night driving is more dangerous than day driving. One reason is that some drivers are likely to be impaired – by alcohol or drugs, with night vision problems, or by fatigue.
Driving at Night
Here are some tips on night driving:
- Drive defensively. Remember, this is the most dangerous time.
- Don’t drink and drive.
- Since you can’t see as well, you may need to slow down and keep more space between you and other cars.
- Slow down, especially on higher speed roads. Even your halogen-beam headlights can light up only so much road ahead.
- Keep plenty of space between you and other vehicles. It’s hard to tell how fast a vehicle is going by looking at its taillights.
No one can see as well at night as in the daytime. But as we get older these differences increase. A 50-year old driver may require at least twice as much light to see the same thing at night as a 20-year-old needs.
What you do in the daytime can also affect your night vision. For example, if you spend the day in bright sunshine you are wise to wear sunglasses. Your eyes will have less trouble adjusting to night.
Sunglasses should not be worn at night when you are driving. They may cut down on glare from headlights, but they also make a lot of things invisible that should remain visible – such as parked cars, obstacles, pedestrians, or even trains that are blocking railway crossings. You may want to put on your sunglasses after you have pulled into brightly-lighted service or refreshment area. Eyes shielded from that glare may adjust more quickly to darkness back on the road. But be sure to remove your sunglasses before you leave the service area.
The eyes can be temporarily blinded by approaching lights. It can take a second or two or even several seconds, for your eyes to readjust to the dark. When you are faced with severe glare (as from a driver who doesn’t lower the high beams or a vehicle with misaimed headlights) slow down a little. Avoid staring directly into the approaching lights. If there is a line of opposing traffic, make occasional glances over the line of headlights to make certain that one of the vehicles isn’t starting to move into your lane. Once you are past the bright lights, give your eyes time to readjust before resuming speed.
If the car approaching you has its high beams on, signal by flicking yours to high and then back to low beam. This is the usual signal to lower the headlight beams. If the other driver still doesn’t lower the beams, resist the temptation to put your high beams on. This only makes two half-blinded drivers.
On a freeway, use your high beams only in remote areas where you won’t impair approaching drivers or drivers right in front of you. In some places, like cities, using high beams is illegal.
When you follow another vehicle on a freeway or highway, use low beams. Most vehicles now have day-night mirrors that enable the driver to reduce glare. But outside mirrors are not of this type and high beams from a following vehicle often bother the leading driver.
A Few More Night Driving Suggestions
Keep your windshield and all the glass on your vehicle clean – inside and out. Glare at night is made much worse by dirt on the glass. Even the inside of the glass can build up a film caused by dust. Tobacco smoke also makes inside glass surfaces very filmy and can be a vision hazard if it’s left there.
Dirty glass makes lights dazzle and flash more than clean glass would, making the pupils of your eyes contract repeatedly. You might even want to keep a cloth and some glass cleaner in your vehicle if you need to clean your glass frequently.
Remember that your headlights light up far less of a roadway when you are in a turn or curve.
Keep your eyes moving; that way, it’s easier to pick out dimly lit objects.
Just as your headlights should be checked regularly for proper aim, so should your eyes be examined regularly. Some drivers suffer from night blindness – the inability to see in dim light – and aren’t even aware of it.