Somehow I have trouble with using 9-11 as an example to illustrate emergency survival behaviours.

One of the problems is that 9-11 was a deliberate and severe bombing attack. That puts it into a class of its own.
The other is that any discussions I have seen about it almost immediately turn into political discussions.

However, even in the 9-11 scenario the people who left made it and those who stayed late were lost.

How the fires started, whether the buildings were knocked over by the planes or if it was all a New World Order or Illuminati plot does not really matter much.

The real point is that nobody had a clue about what was happening and that is the normal situation.
It is true on industrial sites and ships too.
So the thing to do is evacuate as soon as possible.

One thing that I have seen in the news which does worry me is the habit a lot of companies have of locking emergency exits.
I have seen that done in offices, in factories and in nightclubs.

I would also like to mention a bit more about muster points.
If they are well selected they are can be effective refuge station.
Muster points allow you to take a count of who made it out, and hopefully let you know that nobody is left that you need to go back for.
Muster points give your people a definite action plan. They know where to go and go there.
Muster points mean the people have not left work. If it is a false alarm you can get your people back to work after the situation is cleared.
Muster points have more things to recommend them but that is enough to get the idea.