Why would I want to travel to a foreign land and sleep in a metal box?
As a contractor visiting a military base, this might have been your only choice of sleeping quarters. Hotels in the area of your work, provided that you are there for more than just one day, are either not as secure as a foreign traveler would require, or hotels are too far from the work site.
The only option is likely to be a containerized housing unit located within a designated safe zone near the site. Such “nonpermanent” quarters may be grouped in zones with several hundred CHUs and are covered by a separate overhead structure.
Overhead structures in this application are generally designed for seismic conditions and may be installed over the CHUs for various reasons, including reduction of exposure to excessive solar heat load and rain, as well as exposure to flying debris and mortar fire. With this last item in mind, seismic design of all life-safety systems added to the CHUs becomes a necessity, regardless of the seismic zone class of the site. A concussion due to a local blast can be survivable if life-safety systems such as sprinklers and fire detection are seismically braced.