Why not a do-it-yourself air purifier?
It may seem a little Rube Goldberg-ish but a University of Michigan professor has devised a do-it-yourself air purifier that he claims cuts indoor allergens by 90 percent. Made of a cheap box fan and a furnace filter, the contraption costs far less than some of the pricey air purifiers on the market. “This is a filtration system that you can put together with items from your local hardware store for $25 to $30 and use in your home to cut indoor allergens by about 90 percent,” says Jeffrey E. Terrell, M.D., director of the university’s Sinus Center.
As you can see in his video demonstration, Terrell tapes a 20- by 20-inch whole-house air filter (MERV 13 or higher), which sells for $15, over a 20-inch-square box fan, which you can find for about $12. Using a particle counter, he found that his homemade purifier rid the air of particles nearly as well as an $800 machine.
We haven’t tested Dr. Terrell






