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PSA: don't require people to distinguish between red/yellow/green in status LEDs etc. Especially if there is no other way to distinguish status (position of LED, flashing pattern, etc). Red-green color blindness is incredibly common (~5% or so of people), much more common than other kinds of color blindness.
I'm not colorblind so can't give specific recommendations, but it seems that green/blue or red/blue are better options if you have to differentiate by color. While there are people who have trouble differentiating between those colors, it's much rarer than red-green color blindness.