This is a fundraiser for DC Public School buildings that are still short short on HEPA filters for their classrooms and workspaces. There is a DIY device called at Corsi-Rosenthal Cube that is built using four 20x20 MIRV-13 furnace filters and a box fan. It's simple, but it works about as well as a HEPA filter, will function the entire school year, and only costs about $100. You can read details on how they are built and the engineering behind the design here, and here's a pretty good This Old House how-to video on how to make one:
I'm raising funds to build as many of these as possible for DCPS classrooms and workspaces. As of right now, I have "orders" for 5, and I expect many more. First of all, if you know of a school or teacher that might need more air filters, have them fill out this form right away so I can gauge the scope of demand.
Second, please donate if you can. I'm raising $1,000 to start with, which would get us the first 10, but I expect this number to go up. There's a good possibility that the limiting factor will be the number of air filters I'm able to purchase at hardware stores, but we will cross that bridge when we come to it. School starts Monday, let's get this done.
I'm posting more regular updates on this twitter thread , so check there if you want the minute-to-minute.