Empty hospital-hallway

This afternoon I picked up my girlfriend from her work (she works at a hospital). On my way from the parking to the building, I took some nice photo's of a few chimney's with purple-ish lit water-vapour coming out of them. Only the guy from security demanded I wiped these off my camera because these were secured buildings and I didn't have permission. My argument that you could see the same from the street, and therefore it was public, wasn't enough.
So I made some photo's of the hallway inside the building, while waiting for my girlfriend and her colleagues to change clothes.