The orange stuff does look like fire-resistand wiring of some sorts. Here the orange stuff is NHXH E30 or E90 (minutes fire resistant), with an outer sheathing that polymerizes in heat and turns to a ceramic-like substance (but not powder-filled like MICC). Weird idea to use that for an apartment service for sure. Helluva expensive and only used for critical applications here (elevators, safety lighting, sprinkler controls and pump feeders,...)
