Florence Nightingale always wore a white uniform. White, of course, is a symbol of purity, and in the case of a nurse, an appropriate and practical one—white quickly shows any dirtiness.
Surgeons also wore white unitl 1914, when a surgeon decided that red blood against a white uniform was rather repulsive and needlessly graphic. The spinach green color he chose to replace it helped neutralize the bright red.
At the end of World War II, the lighting was changed in operating rooms, and most surgeons switched to a color called “misty green.” Since about 1960, most surgeons have used a color called “seal blue,” which contains a lot of gray. Why this latest switch? . . . [S]eal blue shows up better on the TV monitors used to demonstrate surgical techniques to medical students.
—David Feldman, from Why Do Clocks Run Clockwise? and other Imponderables, 1988.