Are your manager's visits announced or unannounced? How long do they last? Do you plan to place the cabinet in a closet or in the open?

My cabinet is in a small closet with sliding doors. If I turn off the lights and main fan, then move the hanging fan inside directly in front of the cooltube, it maintains enough negative pressure to prevent escaping smell and is nearly inaudible - completely so if a computer is running nearby. When I have guests who might enter that room, I do that and close the closet doors. People have walked within 2 feet without noticing anything. The carbon filter on the unit by itself leaves a trace of an unclassifiable 'sweet' aroma like heated sugar smelled from a distance. Adding two 22-watt odor-killing CFLs to the ceiling fixture completely eliminated even that smell.