Here is another version of the Mini Corsi-Rosenthal Box. It takes about 10 minutes to build. It has a small “footprint”. It is quiet – just 19 dBa. And the fans are rated at 104 cfm. Perfect for an office, bedroom, examining room or any other critical space where two or more people are in close contact. Many people have had trouble finding 9″ or 10″ box fans for the original mini CR box. This is a great alternative at a reasonable price.

Here is how to make it:

Materials needed – 4 MERV 13 10X10X2 Filters, duct tape, a piece of poster board for the bottom, a box cutter and a modular 2 PC Fan system.

More about the modular 2 PC fan system. It has a USB port so the system can be used in an automobile, high occupancy vehicle or connected to a battery. It also has a turbo adapter so that it can be used in all standard wall plugs. Energy usage is 4-5 Watts. Plus it comes as one finished, modular unit – no assembly required.

I used the standard Mini CR Box MERV 13 10X10X2 filters. However, they are a bit small for an exact fit. Pre-build the box allowing for a 1/4″ gap on each end. Secure with 2″ duct tape.
Here is the completed box shape. Note that the side filters are configured to form a rectangle instead of a square.
The finished Modular Mini Corsi-Rosenthal Box. All gaps are sealed with tape. It meets the requirements for an effective air cleaner – Filter + Fit + Flow!

That’s it. Simple to build, inexpensive, quiet, minimal space usage, energy efficient and effective. I am a firm believer that this is an excellent air cleaner. We have one running in our bedroom. It works!