Originally Posted by
Marcel
Where I used to work the discussion on this topic was repeatedly covered numerous times, so I think I have the response down almost down pat...
Red/Green colour blindness is the most common form of human colour blindness with between 15% to 40% of all people suffering the condition in any given community. The Brown/Blue/Green colour combination is the least common form of colour blindness at less than 0.0001% of all people. And it is the founding reason why for at least the past 40 years the IEC recommendation specifies the Brown/Blue/Green-Yellow stripe for flexible cords on appliances. Most countries in the world have adopted and legislated the IEC recommendations as standard practice.
In isolation the simple addition of the Yellow stripe to the Green earth wire improved safety by an estimated 90% as it made the earth wire visibly different to the Red wire as seen by people who are Red/Green colour blind. Including the Brown/Blue combinations improved safety due to mistaken colour identification to near 100% levels... Which only leaves ignorance, stupidity and the individual (obstinate) country based unique antiquated colour systems as the current main three factors contributing to modern day appliance power wiring errors,...