The Reason Traffic Lights Are Red, Yellow, and Green

[Robert59]

All around the country, traffic lights help maintain order on roadways by signaling when it’s time to stop (red), slow down (yellow), or continue (green). While the color scheme appears obvious now, it had to have been created and invented somewhere. Here’s how we arrived at these beacons of the transit system.
https://www.msn.com/en-ca/news/offbeat/the-reason-traffic-lights-are-red-yellow-and-green/ar-BBYyZ8P

 

[Catlady]

Very interesting Robert, thanks!

I do wonder though, since some people are color blind and cannot see the color red, how does that affect them?

 

[JB in SC]

Very interesting Robert, thanks!

I do wonder though, since some people are color blind and cannot see the color red, how does that affect them?

Red is on the top, green on the bottom. That was not always the standard configuration from my understanding. My late father in law was color blind and told us he ran a few traffic lights in his youth because the red and green were opposite in some towns. At least that was his story.....

 

[Aunt Bea]

And one reason why they are not all red, yellow, green.



https://www.syracuse.com/entertainm...s_it_to_hit_the_green-over-red_stoplight.html

 

[Pappy]

Then there is always these:

 

[oldman]

Did you know that the colors of the lights at the airport also have meaning? And, depending what color lights are lit and the location of the light is on the outside of an airplane, allows those that work out on the tarmac and in the tower, the status of the aircraft.

On the airfield, you will see red, amber, blue, green and white lights. Each light represents what the distinction of the roadway is.

 

[fmdog44]

I have years of proof stop signs and lights and basically all regulatory traffic signs do not work. Just saw another example this afternoon.

 

[fuzzybuddy]

I disagree. they are not red, yellow, and green. They are red, yellow, and blue. All the lights around here ( Northeastern PA, US) have blue lights. And no they aren't some shade of green, but blue.