Room 1: The Waiting Room (someone will be hiding under a desk, we'll have a TV playing static, chairs, etc.)Welcome to the forum
You'll need to explain more about what you have as far as props and theme(s).
You do, however, have to be careful about anything actually falling on a guest unless you as the haunter want to experience the fear of a lawsuit.One other big thing that scares everyone would have to be a falling wall or ceiling. With something that crashes on top of you, you don't have to believe a storyline, actor, or anything for it to be scary; it just is.
Perhaps I should rephrase what I said in more detail.Stuff falling on you?
Hope you have a really deep treasure chest for the lawsuits that will follow. There's no way the fire or safety authorities, much less the insurance people, would ever allow you to do it, or cover you for that kind of thing if you are doing it on purpose. Why not just pump in poisonous gas, that would surprise them too, then they can trip on the bodies of the people who came in before they did?
Don't give people crazy ideas that things like this are even thinkable. This is up there with fake razors (or real ones for that matter) are okay to put in treats for the TOTs.