Do you just get the basic color red green yellow for trainservice test? Do you have to know all the colors shaded? Please explain!!
For the BNSF you'll need to be able to pass a color vision test in order to be hired. As far as working, you'll need to know red, green, yellow and white. In service, you'll need to know what the colors mean as well as combinations of colors such as red over green, red over yellow and so forth.
Good luck.