If you are concerned about the risk of COVID, RSV, the flu, and poor indoor air quality at work, school, or home (especially if people are infected and want to reduce the risk of spread to other household members) but cannot afford to buy expensive HEPA air purifiers, fret not–you can build your own air cleaner with a box fan, some MERV-13 furnace filters, cardboard, and masking tape!It’s called a Corsi-Rosenthal box and it is a much more accessible and economical way of cleaning the air than replacing your air conditioning and ventilation units, or buying a bunch of HEPA air purifiers.
Source: Build a DIY air purifier! Tickets, Sun, Dec 18, 2022 at 4:00 PM | Eventbrite