Why do pedestrian crossings have two red lights in some cities (Oslo, Cologne)?
I met traffic signals with two red lights in several European cities: Oslo, Cologne. Do you know why they are doubled?
Cologne
OsloI found several possible explanations.
1. Originally they had two red ones in case on of the light bulbs went out, and they didn't want people to think the traffic light was out of service. That is, one of the red ones would still be glowing. This stuck when they changed to LED-light. And then they found out at that it gave more security since it made the red light more visible, so they just kept using it.
2. As an extra bonus this helps color blind and old people read which signal is up. They may not know what color the signal is on, but they can look at the number of men.
3. Someone just bought a bunch of traffic lights and they were re-purposed as walk/don't walk light and the second don't walk was used so it didn't look broken.
Even more unusual traffic lights you can see in this video with good music.
If you like this video, please, visit my youtube channel