Regarding the original question, first thing is to check the preps, check everyone , assess the situation, then make a plan.
Preps should have already been checked before the incident happened. It's too late to make a plan unless you mean a plan to deal with a specific situation that had just happened.
Other than looking at the ceiling, I would focus on checking and maintaining the facilities that help us survive like water sources ..etc.
Things like water purification were covered in the opening post.
Jeanette Isabelle