CleanAirKits - Brisk Box (CleanAirKits)

I'm using the CR boxes, and I'm very happy with them, especially since it cost me less than $200 to make three huge ones, and I assume the filters will last years.

Yeah absolutely.  I don’t mind a little noise, but on some of these air purifiers to get the CADR that makes sense, you need to blast them.  I recently bought a PC fan air purifier from clean air kits. They t won’t win any beauty contests but it moves a tremendous amount of air with very little noise. 

You can make a Corsi Rosenthal air filter. Check out the instructions on youtube. They work as well as industrial air filters.

A [CR box](https://corsirosenthalfoundation.org/instructions/) (Filtrate 1900 or MERV 13 furnace filters and a box fan) is your best option: they're cheaper and more efficient than commercial air filters; because the filters are just furnace filters, you can get them basically anywhere; and they can be designed in lots of ways to suit your space (the standard 4-filter design, two filters in a triangle shape with the fan as the third side, one filter with a spacer between the fan and filter, two or four filters with computer fans for quieter filtration, mounted to a wall like a floating shelf, etc). Look online for pictures and further instructions for different shapes.

First off, "best" is whatever has the highest CFM rating. Whatever pushes the most air is pretty much best. Corsi Rosenthal boxes are "best" as they can easily push 1000 CFM. But in reality you choose based on other metrics, such as price range, availability of filters, price of filters, how often they have to be changed, how quiet they are and so on. I picked a Philips 4200 Pureprotect, to me this was best, as it was high CFM rating, auto setting and very quiet. While also having new filters available in my market for years to come. And personally I've tested it at home, where I don't notice much of a difference as air qualiy was pretty good in the first place. But also in the homes of friends who have dogs and I have asthma and react to them. Had a friend set it up a few days before his birthday so the air would be properly cleaned for a few days when I got there and it made a huge difference. Usually I notice symptoms after just a few minutes, this time I could spend hours at his house with minimal symptoms. But even if my unit is a quite expensive, good and quiet unit it still doesn't get close to the Corsi Rosenthal DIY boxes in terms of how much air is purified. Hope this helps, just keep filter price and exchange rate as well as availability in mind when you buy one and you'll be fine. And remember more air is better, filtration efficiency matters a lot less than just the air volume.

Corsi Rosenthal box. Fuck proprietary (and often expensive) filters.  Mine are from Clean Air Kits and they are stupid quiet, I can run them off a battery pack in case of power outages cause they are super cheap in terms of power usage and I can get furnace filters cheap.  We have two dogs (one of whom has nasty allergies to pollen) and they make a huge difference.  We have one per floor but make sure they are sized for your space. 

Three words. Corsi Rosenthal Box.

If you look at cost, CADR/CFM, and noise, nothing on the market beats [Clean Air Kits](https://www.cleanairkits.com/?ref=CCCircle), period. Data to back it up, any entry in gray is a setting that is louder than 50db: [https://docs.google.com/spreadsheets/d/1kQMWNyKfkB0K8A4\_yXMrSAb-CruVl9lASJEpLGLtS8o/edit?usp=sharing](https://docs.google.com/spreadsheets/d/1kQMWNyKfkB0K8A4_yXMrSAb-CruVl9lASJEpLGLtS8o/edit?usp=sharing)

Thirding air purifiers! I finally gave in and traded my two big winix HEPA guys for a gigantic corsi rosenthal box made of four 20x20x4-in home AC filters. It's much louder but the performance is out of this world, and the filters last forever now. My two 1,200sq ft rated filters struggled in my 500sq ft space with even monthly changes (desert life, lots of animals, massive grading project nearby, endless dust), but this one box handles it no problem, and for many months now.

I made it, just crudely taping some whole house filters onto a box fan. It won't be fun to tape up again when I need to replace the filters, I need to create a proper design that's easily maintained, but this was a proof of concept. It's been several months and it works perfectly.

Not pretty but very effective  Corsi–Rosenthal Box - Wikipedia https://share.google/VT90TcVB763kaVmSa

They work very well. When covid hit i looked for a way to try and address aerosol transmission as someone who has never caught a light cold or had a touch of the flu in my life. If i get sick i get very sick. I put together 2 of these and bought a CO2 and a particulate air monitor and i was amazed at how dirty those filters would get in just a matter of months. After a while i bought filters that use PC fans because they are much, much quieter. I was lazy and bought them but if you are a little bit handy you can put them together yourself. [https://www.youtube.com/watch?v=wS0LK\_LiqmE](https://www.youtube.com/watch?v=wS0LK_LiqmE) The ones i bought come from here if you have the funds: [https://www.cleanairkits.com/](https://www.cleanairkits.com/)