Originally Posted by
Bah Humbug
And for
jtaylor996, if the reason some traffic signals are horizontal is because of wind, then I'd say they all need to change when replaced. It is really not good to have safety items like that be non-standard.
Well, it's one reason. Also better clearance for trucks, and more modular. In TX they put an actual horizontal member above the lights to add lift in wind, and I think it has a label on it so rescue heli's can tell where they are without GPS. They put all sorts of interesting things on the poles around here. It's quite the rabbit hole.
There's a saying though: "The good thing about standards is that there are so many to choose from!". There is a US standard for lights, and it allows both configurations, just to back that quote up.