USE OF HEADLIGHTS 22-201.1
A driver is required to turn on the headlights of his vehicle whenever an object cannot be clearly seen at a distance of 1,000 feet ahead. It is also required that you turn on your headlights whenever your windshield wipers are in use due to rain, fog, snow, etc. This would be true no matter what time of day it is.
LIGHTS IN HEAVY FOG, RAIN, OR SNOW
When lights are necessary due to heavy fog, rain, or snow, the low beam headlights would be the most effective for illuminating the roadway. This is because less light is reflected by the hazard.
WHEN TO DIM 22-223
Whenever the driver approaches an oncoming vehicle within 500 feet, the lights shall be turned to the lower beam. When following another vehicle within 300 feet to the rear, or when passing, he/she shall put the lights on the lower beam.
If the driver of an approaching vehicle fails to dim his lights, blinding your vision, look to the right, away from the bright lights. Do not change your lights to the high beam, since this will block the vision of both drivers, increasing the probability of having an accident.
SPEED AND LIGHTS
Statistics reveal that most fatal accidents happen at night in clear weather and on dry highways. The combination of lack of visibility and driving too fast, is the major cause. Everyone should be aware that it is more dangerous to drive at night because you cannot see as far ahead even with the high beams on. A driver should adjust his speed so as to be able to stop the vehicle safely within the distance of his visibility at any time.” “