Corsi-Rosenthal boxes rely on filters and thus are passive technology. This means they must wait for contaminants to pass through the filters in order to be effective. ActivePure Technology is active purification, which means it meets and neutralizes contaminants out in the room.
One must also consider space. The very largest ActivePure machine (designed for large public spaces such as gymnasiums) takes up a little over 2 cubic feet of space. A Corsi-Rosenthal box with a 20-inch box fan would take up over twice that. Because of this ActivePure Technology can be installed in elevators, buses, cars, and right inside HVAC systems, while Corsi-Rosenthal boxes cannot. This is not to say that Corsi-Rosenthal boxes don’t make an excellent, economical way to reduce pollen, smoke, and dust. However, as many purifiers with ActivePure Technology include a HEPA filter, they render Corsi-Rosenthal boxes redundant.