This is a pretty common staircase type where I live but how do I map it? Should I make lines over each other multiple times, each with different level? Or just one line and don’t care about the other floors? I don’t know if I’m searching for wrong terms but I have a surprisingly hard time on getting info about stairs mapping.
Can you point me to the right direction or post some example?
No, it is not. OSM is a database of geodata. The rules are clear: what is in there, must be (semi)permanent and observable. A fire staircase meets those requirements.
If you (or a dataconsumer) doesn’t care about this data, they can simply take a copy and delete from that copy what they don’t need.