Figure 1: Kinda/Sorta air purifier from easy parts.
I wanted a room air purifier (I don’t know if there is a legal definition for such a thing, so mine is a “kinda/sorta” air purifier). I found replacement cylindrical HEPA filters on the internet for about $40. I plugged a small blower into the end of one of them (85 CFM, which is “cubic feet per minute”). Voila – a kinda/sorta DIY air purifier was born. However, it takes a long time to reduce the particulate count (to my satisfaction), so I’ll probably upgrade to a commercial unit, or get a bigger cylinder.
Note: No expert here so none of this is advice: *especially* the duct tape!
Homemade Miscellany 