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Is smoke in your home? Here's how to make an air purifier from a box fan
NPR ^ | January 10, 2025 | Bill Chappell

Posted on 01/11/2025 10:21:39 AM PST by BenLurkin

All you need is a box fan, good air filters and some duct tape, and you're in business.

NPR has previously posted a design and guide to building an air purifying cube known as a Corsi-Rosenthal Box, using four 20-inch MERV 13 filters, a 20-inch box fan and two 20-inch panels of cardboard.

A smaller and more affordable approach is to attach one MERV filter to the back of a box fan, an idea laid out in a website from the Montana group Climate Smart Missoula. The group notes that people using that option should use newer box fans, and be sure the motor is clean to reduce the risk of overheating.

The Centers for Disease Control and Prevention says these DIY purifiers can be effective for a temporary solution, especially if you don't have any other alternatives.

Search filters by their MERV rating Filters are key, whether you're using them to upgrade your home's HVAC system or put them in an air purifier or a DIY air cleaner. A filter's ability to pull particulates and other matter out of the air are rated by Minimum Efficiency Reporting Values, or MERV. Filters with higher values can catch smaller contaminants like smoke, bacteria and viruses.

A MERV rating of 13 means the filter is efficient at catching items from 0.3 to 1 micron in size: "Bacteria, droplet nuclei (sneeze), most tobacco smoke, insecticide dust," according to the California Air Resources Board, or CARB.

"Upgrading to a filter rated MERV 13 or higher can be especially important during smoky periods to effectively remove fine particle pollution from smoke in the indoor air," the EPA says.

(Excerpt) Read more at npr.org ...


TOPICS: Miscellaneous
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1 posted on 01/11/2025 10:21:39 AM PST by BenLurkin
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To: BenLurkin

Ingenious. Noisy I’m betting, but effective I would think.


2 posted on 01/11/2025 10:35:46 AM PST by ChildOfThe60s (If you can remember the 60s, you weren't really there)
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To: BenLurkin

CARB.... Giving advice in a state where they have 300,000 houses without power because of their insanely stupid policies.....


3 posted on 01/11/2025 10:58:49 AM PST by Organic Panic (Democrats. Memories as short as Joe Biden's eyes)
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To: BenLurkin

Folks in Montana do this every fire season.

My church down South has gone up to Montana and one of our projects were to take donated fans and filters and put them together for the poorer communities.


4 posted on 01/11/2025 11:00:31 AM PST by Nathan _in_Arkansas (Hoist the black flag and begin slitting throats. )
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To: BenLurkin

Here is how I did it years ago. On a window fan, on the back side place a foam rubber filter. Once in place it will work well. to make it work better spray some non stick spray cooking oil on it but not a lot or you can plug the filter in a day.
I learned the cooking spray trick in power plants where they used it to catch dust on incoming air fans.


5 posted on 01/11/2025 11:29:15 AM PST by Ruy Dias de Bivar
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To: BenLurkin
For a quieter, more efficient Corsi-Rosenthal Box, use several computer fans instead of a window fan. You can do it yourself or buy a kit from www.cleanairkits.com. This link has versions with 4 or 6 fans, and links to get low cost filters.


6 posted on 01/11/2025 12:28:32 PM PST by UnwashedPeasant (I The pandemic we suffer from is not COVID. It is Marxist Democrat Leftism. )
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To: UnwashedPeasant

That is pretty cool.Ingenious. And cost effective. Gotta be a lot quieter than a box fan.


7 posted on 01/11/2025 3:19:59 PM PST by ChildOfThe60s (If you can remember the 60s, you weren't really there)
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To: UnwashedPeasant

Bkmk


8 posted on 01/11/2025 6:17:44 PM PST by Ignatz ("Look, if I offend anybody today, I don't care." -Tom Homan)
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To: BenLurkin

OR you can do like we do: install a 5” MERV-13 filter in your furnace filter compartment and turn your forced air furnace circulation fan to “manual” [with or without heat or cooling] during a high particulate event such as large volumes of forest fire smoke arriving from remote areas ...


9 posted on 01/11/2025 6:37:50 PM PST by catnipman ((A Vote For The Lesser Of Two Evils Still Counts As A Vote For Evil))
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To: BenLurkin

How is this any different than setting your AC to fan mode (assuming it’s using MERV 13 filters also? If anything the AC fan is likely more efficient, has greater airflow rate, and provides whole-home air flow, not just filtering a small area in one room..


10 posted on 01/11/2025 7:26:28 PM PST by Svartalfiar (-)
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To: ChildOfThe60s

How is it cost effective?

I would guess that an AC in fan mode usus less power per volume of air than a fourpack of computer fans or most box fans, while the AC is also whole-home but this contraption only works on one side of a single room


11 posted on 01/11/2025 7:41:06 PM PST by Svartalfiar (-)
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