Re: Colour
Mains cable colour coding is a classic example of CVD changing things worldwide.
Black/white/Green is as dangerous as red/black/green when some people can't see red (it shows somewhere between brown and black) some can't tell the difference between red and green (they both show as brownish) and CVD testing was never part of electrical training.
Brown / blue / green-yellow stripe can be distinguished by virtually ALL people regardless of CVD
I don't have any CVD, but my father does and the area that I'm from has somewhere between 1/4 and 1/3 the male population suffering from red/green colourblindness. This stuff got drilled into us because it kills people.