Not just the workplace. When you go anywhere you should always ascertain all the exits you can. Not just for terrorism but for lots of other disaster scenarios such as a fire. The first rule of self defense is situational awareness.
I watched a movie years ago (don’t even remember the name) where a guy and gal were having lunch or something and he says...what do you see? She looks around and says I don’t know then he proceeded to tell her what everyone around them was wearing and doing. Don’t know why but it stuck with me. Ever since when I go somewhere I see how much I can remember...exits, people, etc. before I sit down. Kind of a game I play in my mind. Never thought it would be useful. What a shame.