# I Simple suction air filter: items and preventing implosion

1. Dec 23, 2016

### r19

I want to make a simple air filter(for dust and air pollution) but was a bit confused about some stuff. Basically I've decided to use an exhaust fan to create a vacuum in a sealed box and the air to come in through the filters. Box fans aren't available here, so that can't be used. I want to create a 'CADR' of 250(CFM is not accurate benchmark of purifier performance, since air might repeat through the system). Such filters are available here for 150$, so though this will not save much money(time) for me it could be helpful for other people here. Total cost would be 40$.

>I'm thinking of going with a 40db 8in 1400rpm fan, 450CFM. I've used this to get an idea of relationship between CFM and CADR - http://www.theairpurifiers.com/air-purifier-performance.html . A 6in 250CFM fan might be fine but not sure