During which decades did the adoption of the universal red-yellow-green electric traffic light sequence become standard?

Answer

1920s and 1930s

The standard red-yellow-green sequence solidified its position as a universal language for intersection management through widespread use during the 1920s and 1930s.

During which decades did the adoption of the universal red-yellow-green electric traffic light sequence become standard?
inventiontechnologytransportautonomyintersection