Thread by @lisawhelan

This is a next gen DIY air filter I built for #California #wildfire season, leveraging a design from @AbraarKaran & @sri_srikrishna. I used foam core instead of cardboard for the shroud, which makes it look pretty. Big size improvement on #CorsiRosenthalBox & air smells great! /1

Here's the side view. I sliced a 7" circle in the center of 30" foam core (@DollarTree via @Instacart) & duct taped a 16" pizza screen (@Walmart) inside to protect toddler fingers. I sliced a straight cut half way through the foam core at 4.5" from each side w/ an Xacto knife. /2

This made it easy to wrap foam core around the sides. Probably could have made this look prettier w/ Velcro (@sri_srikrishna @AbraarKaran used in their design) or 2 sided tape, but I used white duct tape b/c I had a ton left over from a past #CorsiRosenthalBox extravaganza. /3

I purchased a 5 pack of @LennoxAir 7935 Healthy Climate filters at @Furnace_Filter for $448.51 ($89.70 each- best legit price I could find) & used 20" @Lasko_Products box fan from @walmart (via @Instacart ) /4

Word of warning: Interlight is falsely advertising a better price than @Furnace_Filter on @LennoxAir 7935 Merv 16 filters via @Google, but I received off brand Merv 11 filters instead. So stick with a reliable vendor. I've used @Furnace_Filter 2x with success. /5

In a paper published by @AbraarKaran @sri_srikrishna in @sciencedirect, a @LennoxAir 7935 on a box fan has a clean air delivery rate (CADR) of 405-645, depending on the fan speed- WAY better than any of the top store bought air cleaners they tested: sciencedirect.com/science/articl… /6

The DIY filter configuration from @AbraarKaran @sri_srikrishna is a lot smaller than a typical #CorsiRosenthalBox & more aesthetically pleasing. It also doesn't require adding feet which is nice. /7

Based on my experience, it also seems a lot quieter. I don't have a DB meter, but the new version sure sounds quieter in my amateur side by side comparison. /8

Anecdotally, this DIY air purifier seems to clear the smell of wildfire smoke from my house better than the #CorsiRosenthalBox models I made last year. The @LennoxAir x7935 is a carbon filter, which IMO makes air smell noticeably better. I use the same brand in my home HVAC. /9

For more info, check out:

https://twitter.com/AbraarKaran/status/1551392210561540096?t=G5kQ4W3jXGM9HKQuL9dJ6A&s=19

Huge thanks to @AbraarKaran @sri_srikrishna @CorsIAQ @JimRosenthal4 @kprather88 @marwa_zaatari @linseymarr @jljcolorado @ChemDelphine for the life-saving info on filtering air for covid & #wildfire smoke these last 2.5 years! /End

To clarify, the radius is 7". The diameter is 14"