If anyone is into architecture you may notice how this kind of stairs were frequently used in buildings built in the late 20's or 30's here in italy.
Here's a shot from the administration building of an abandoned explosive factory near where i live.
As you can notice the staircase is quite the same, maybe a bit bigger.
And this one is from a chemical/artifical fibre factory near milan. Too bad i don't have a better shot of this one, but you can see that the stair goes on like this one and there are the same windows made with glass concrete.