«AAA’s test results suggest that
halogen headlights, found in over 80 percent of vehicles on the road today, may fail to
safely illuminate unlit roadways at speeds as low as 40 mph. ...high-beam settings on halogen headlights...
may only provide enough light to safely stop at speeds of up to 48 mph, leaving drivers vulnerable at highway speeds...Additional testing found that while the advanced headlight technology found in
HID and
LED headlights illuminated dark roadways 25 percent further than their halogen counterparts, they still may fail to fully illuminate roadways at speeds greater than 45 mph. High-beam settings on these advanced headlights offered significant improvement over low-beam settings, lighting distances of up to 500 feet (equal to 55 mph). Despite the increase,
even the most advanced headlights fall 60 percent short of the sight distance that the full light of day provides.»