If you stand outside the 3rd floor cleanroom, you'll be looking through these windows.  Below, work is ongoing to install the metrology wall: a rail for power, data, nitrogen/air/vacuum where tables and table-top metrology instruments (e.g. for film thickness measurement) can be placed.  We put those tools along the wall, because they don't need a chase space, and because they are easily accessible from all bays in the cleanroom.