Ha Rav, Can we sit on other people’s furniture in our building’s bomb shelter? We do not know whose furniture it is?
My assumption is that you mean to ask that during an air raid siren and you are waiting in the bomb shelter, are you permitted to sit on chairs or a couch that was left in the bomb shelter. The answer is that yes, you may sit on the furniture. This is for a number of reasons. First of all, it is safe to assume that a person doesn’t mind of someone sits on his chair or couch, in a way that will not ruin it. Secondly, it is quite possible that the person doesn’t even want the furniture that is there, as it is quite common for people to put things in a bomb shelter, that they don’t need anymore, and forget about it, but they have no intention of even using it again. Therefore, you may sit on them.