I spent some time at the remaining facility in the country making the really interesting rocket fuel. The most fascinating thing to me (aside from the multiple armed security checkpoints required to visit the food lab we were visiting) was the setup of the buildings. Nearly all of them were ~500yds apart, set in between massive ~50ft tall, ~100ft wide earthen berms. The really interesting buildings had escape slides coming from the second floor. Each building at the roadside had the familiar NFPA diamond for response crews. I've never seen so many "4"s on that diamond in my life.
I used to work at a pilot plant that did large scale synthesis of pharmaceuticals. The plant was a concrete structure with each reactor surrounded on three sides by two foot thick concrete walls.
The interesting thing was that there was no outside wall to the building, just a woven steel curtain. If something did explode you wanted a path for the debris. On the outside of the building was a curved ramp, like a skateboard half-pipe. That way any explosion would be directed upward rather than outward.
My favourite chemical bunkers are the ones with a couple of feet deep gravel on the roof. So if there is an explosion, the resulting fire is smothered I assume.
