Yes I gathered you are on the 3rd floor according to your first post.
But I don't see myself running down the stairs from my 3rd floor apartment with 3 pet carriers containing each 3 cats (considering that certain cats don't really get along to share a pet carrier...)
When you are living at ground-level it has a tendency of keeping things more or less simple compared to apartment living. I was just thinking that the quandary you're in might be better addressed by your local fire station. Being an apartment block they will have had to have done fire inspections of the property in the past, and they should be able to shed some light on your problem. Depending on the structure whether it is framed or masonary, which would dictate the speed of fire will dictate the procedures required to save the animals, and the boys at the fire hall could be your best bet for getting answers to your question.
I am glad you brought the subject up. It's something we all should think about, but as I said before it only happens to the other guy. If you decide to check out the fire department I would be interested in hearing what they suggest.