I used to work on Tempest machines in a SCIF. The pink noise generators in the airducts to prevent listening devices drove me nuts.
Shielding the keyboards, monitors, and cables for H fields was very difficult. I used to set up a spectum analyzer and recorder and crawl the cables with probes. Without TEMPEST, I could record everything right off the cables. Government and private industry should both be using that shielded room wallpaper on the walls/ceiling/floor, then a shielded door to each office.