School bus yellow is a color that was specifically formulated for use on school buses in North America in 1939. The color is now officially known in Canada and the U.S. as National School Bus Glossy Yellow and was originally called National School Bus Chrome. The pigment used for this color was, for a long time, the lead-containing chrome yellow.
The color was chosen because it attracts attention and is noticed quickly in peripheral vision, faster than any other color. Scientists describe this as follows: “Lateral peripheral vision for detecting yellows is 1.24 times greater than for red.”
In April 1939, Dr. Frank W. Cyr, a professor at Teachers College, Columbia University in New York organized a conference that established national school-bus construction standards for the U.S., including the standard color of yellow for the school bus. It became known officially as “National School Bus Chrome”. The color was selected because black lettering on that hue was easiest to see in the semi-darkness of early morning.
The conference met for seven days and the attendees created a total of 44 standards, including specifications regarding body length, ceiling height, and aisle width. Paint experts from DuPont and Pittsburgh Paints participated. Dr. Cyr’s conference, funded by a $5,000 grant from the Rockefeller Foundation, was also a landmark event inasmuch as it included transportation officials from each of the then-48 states, as well as specialists from school bus manufacturing and paint companies. The color was adopted by the National Bureau of Standards (now the National Institute of Standards and Technology) as Federal Standard No. 595a, Color 13432.
The conference approach to school bus safety, as well as the yellow color, have endured into the 21st century. Dr. Cyr became known as the “Father of the Yellow School Bus.”
The source: Wikipedia