take into consideration that a high percentage of colour blindness involves the red spectrum
True and most colourblind people have trouble differentiating between red and green.
Do you know how they overcome this with traffic lights?
Next time you look at a set of lights you will notice a tinge of yellow has been added to the red, the one in this pic is almost orange.
Orange lights are basically yellow.
They also did the same with green lights, look closely and you'll see a tinge of blue has been added to the green.
Thus colourblind people are actually spotting the differences between orange, yellow and blue.
Not sure if it was done back in the 60's and 70's but I suspect today's brake lights would be the same.
Even still, a flashing light whether orange or red would still be visible from behind.
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