In good weather, low beam headlights allow a driver to see about 250 feet ahead, while high beams allow 350 to 500 feet of visibility. Vehicle speed may need to be adjusted to ensure stopping within that distance. Dirty or poorly adjusted headlights can cut illumination by as much as one half. High beam headlights should only be used when it is safe and legal to do so. If an oncoming vehicle is using its high beam headlights, look at the white line on the right side of the road rather than directly at the lights. This will offer some protection from the glare and enable your eyes to adjust more quickly once the vehicle has passed.
Roadway hazards that drivers face at night include:
- Poor visibility – at night, hazards aren’t as easy to see and may not be recognized as quickly as during the day
- Lack of route familiarity – though caution should be used on all roads when driving at night, you should slow down and use extra caution on unfamiliar roads to allow enough stopping distance
- Impaired drivers – impaired drivers are a hazard to everyone on the roads. If you come upon someone that appears to be impaired, give the impaired driver plenty of room and remain alert. Use extra caution around closing time for bars and keep an eye on vehicles that:
- Weave from lane to lane
- Stop without reason
- Have trouble maintaining a constant speed
- Show other signs of impaired or erratic driving
- Other road users – in many cases darkness impairs a driver’s view of other road users including those who jog, walk, or ride along the side of the road. A driver should keep an eye on both sides of the road and be alert for reflections of an animal’s eyes or movement.
Fighting fatigue is also a factor when it comes to safe driving, especially at night. Fatigue can reduce reaction time, judgment, and concentration. Signs that indicate fatigue may include:
- Lack of alertness
- Poor memory recall
- Intermittent/erratic shifting
- Lane deviation