Article posted Thursday, July 23, 2015 4:12pm

Why aren’t all fire engines painted red? Public safety records and other studies show that red or red-and-white engines are more likely to be in an accident than a lime-yellow engine. Lime yellow is easy to see during the day because it falls in the middle of the visual spectrum, where we rely mainly on one type of retinal cell. At night, lime yellow is perceived by a more sensitive type of retinal cell, whereas red is not as easily perceived. (Scientific American Mind, Nov./Dec., 2014; Solomon and King, 1997, Ergonomics In Design, Apr. issue)