A further anecdote, I am also (slightly, not absolutely) red-green colour blind. Although I can distinguish between bright reds and greens, darker shades or in lower lights, I am unable to discern between reds and greens.
I'm not always aware that there is a colour I have not correctly perceived, and may simply think that a colour is 'brown', where others clearly perceive it as red or green. However, it's very rare that this causes me problems. I suppose electrical work in low light might be risky, but then I would be taking extra steps to ensure I did not screw up (increasing lighting, asking someone to double check before I touch anything, etc.).
I'm not always aware that there is a colour I have not correctly perceived, and may simply think that a colour is 'brown', where others clearly perceive it as red or green. However, it's very rare that this causes me problems. I suppose electrical work in low light might be risky, but then I would be taking extra steps to ensure I did not screw up (increasing lighting, asking someone to double check before I touch anything, etc.).