Which is why [Adam Kelly] decided to design this DIY HEPA air purifier ... “lid” which would position the fan so it draws air through the center of the filter. In terms of testing, [Adam ...

He recommends placing the filter on the back of the box fan, the air intake side ... To learn more about DIY air purifiers visit the Gonzaga University Institute for Climate, Water, and the ...

However, box fans are not designed for this purpose, and their motor has to work much harder to pull air through a filter, so these homemade air purifiers present an increased fire risk and should ...