Good day everyone!

I am a woodworker in need of information. Woodworkers or not I am sure you all know that in a woodworking shop you end up with a lot of dust. My shop is a small basement shop, about 1250 cubic feet. Despite trying to collect the wood chips and dust at the source an alarming amount of dust still remains floating in the air for a long time.

As many other woodworker, I would like to build my own air scrubber. Generally from a recycled squirrel case blower, mine is about 300 to 500 cfm, a few layered furnace filters (coarse on the outside followed by a mid range one and sometime a higher quality one on the outfeed side). Generally I believe it is recommended to change the air in a wood shop 6 to 10 times an hour, So 500cfm should be quite sufficient.

What I am planning is to use commonly available 16x25x1 filter. But people on the woodworking forum say that these can get clogged very fast. Probably depending of the blower driving them I would assume. But it made me think about doubling the filter area by using 2 opening of 16x25 instead of one, but that would also reduce the airflow on the face of the filter area by two. That is the CFM per square inch so to speak.

So it occurred to me that there must be a lower limit as to the CFM that must pass through a filter for it to be efficient and probably an upper limit also. What would this limit be? That is more for general knowledge, I guess what I really want to know is Should I double my filter area or stay with one with my little 500CFM blower?

Thank you very much in advance for your help and assistance.