Why Lime-Yellow Fire Trucks Are Safer Than Red
Picture a fire truck and you are likely to see red - fire engine red. But when it comes to safety, human factors and ergonomics research paints a different picture. Much of human factors and ergonomics research relies upon psychological research done on human visual and auditory perception. This research shows that because the color-transmitting cones in our eyes don't work well in the dark, some colors are easier for us to see at night. We are most sensitive to greenish-yellow colors under dim conditions, making lime shades easiest to see in dim lighting.
Researchers Stephen S. Solomon and James G. King (volunteer firefighters themselves) were aware of these perceptual differences when they analyzed accident data from the Dallas Fire Department. In the 1970's and early 1980's, the City of Dallas started replacing its all-red fire vehicles with lime-yellow fire vehicles with white upper cabs. After the early 1980's, the fire department bought red vehicles with white cabs. During their four year study published in 1995, Solomon and King found that the risk of a visibility-related, multiple-vehicle accident may be as much as three times greater for red or red/white fire pumpers compared to lime-yellow/white pumpers. The results also show that when lime-yellow/white fire emergency vehicles are involved in an accident, the likelihood of injury or towaway damage is less than for red or red/white vehicles involved in an accident. An earlier study by Solomon involving nine cities and 750,000 fire-vehicle trips found that lime-yellow fire pumpers were half as likely as red fire pumpers to be involved in intersection accidents.
Solomon, S. S., & King, J. G. (1995). Influence of color on fire vehicle accidents. Journal of Safety Research, Vol. 26, pp. 41-48.
Solomon, S. S. (1990). Lime-yellow color as related to reduction of serious fire apparatus accidents: The case for visibility in emergency vehicle accident avoidance. Journal of the American Optometric Association, Vol. 61, pp. 827-831.
American Psychological Association, October 23, 2003