Triple Exhalaron

https://www.cleanairkits.com/products/exhalaron Or https://www.cleanairkits.com/products/triple-exhalaron-stylish-compact-for-medium-rooms I had one in my old econobox and it cleaned up the car inside air super well during all the bad air days we’ve had. Runs off USB-C so I plugged it into a USB cigarette lighter adapter.

If you're driving a car that you own, then upgrade the cabin air filter to a HEPA filter if you haven't already. Keep the car's fan running as it brings it quite a bit of fresh air. I've seen this ventilation keep the interior's CO2 levels near outdoor air levels or just above even with 2-3 people in the vehicle. Then I've used a Clean Air Kits Exhalaron in the middle of the back seat to mix/filter the air that's farther away from the vents.

Look up corsi-rosenthal boxes. I just built one last week and I'm way happier with it than my levoit.

Corsi-Rosenthal boxes are what they're called! I have a lot of allergies and I use one of those. They're great.

How handy are you? A Corsi-Rosenthal box is pretty easy to construct out of a box fan and 4-5 filters. Or I've seen ones that use 2 filters and some computer fans that run quieter.

Its ugly as sin and huge, but I made a CR Box and it is the best HEPA I've ever owned. They were invented during COVID to help reduce viral particles in the air but they have proven useful for any kind of indoor air quality improvement like fire smoke, dust, allergies, etc.... [https://engineering.ucdavis.edu/news/science-action-how-build-corsi-rosenthal-box](https://engineering.ucdavis.edu/news/science-action-how-build-corsi-rosenthal-box) Editing to add the other helpful thing (besides replacing furnace filters regularly) has been to increase vacuuming. I got a really great vacuum - a Miele C1 - and I've noticed much less overall dust since I got it and started a regular vacuuming rotation.

This is true. Web-search for a "Corsi-Rosenthal box." Actually more effective than most commercial air purifiers because it moves much more air. It's simply several MIRV-13 furnace filters taped to a cheap fan.

Corsi-Rosenthal box. You can make one yourself, or buy the kits. The ones with computer fans are wood or metal and will last forever, and because it uses MERV-13 furnace fans you only have to replace them every few years.

Depending on where you are you can spend way less and get good stuff. It really depends on how dirty the air is and how clean you want it. **H**(igh)**E**(fficiency)**P**(articulate)**A**(ir) filters are good because they capture more particles than others. Below them are MERV filters rated 1-16, and [as you can see here](https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating) anything less than 12 nabs under 80% of PM2.5 and imo isn't worth it. These are also more common in home HVAC from what I've seen as well - for mobile units, it's either HEPA or "HEPA-type" which means nothing. If you want the most efficient unit and to spend next to no money, [Corsi-Rosenthal boxes](https://corsirosenthalfoundation.org/instructions/) are the way to go - you need to be able to build and rebuild them, and tolerate a decent amount of noise though. Otherwise, the size of your rooms matters. BlueAir, Coway, Honeywell, Lasko/GermGuardian, Levoit, and Smart Air are some brands that are reputable and have a range of units and sizes. Keep in mind most purifier marketing advertises performance on only the **highest** setting, while advertising noise on the **lowest** setting. Most makers do not have data on other settings, though there are rare exceptions [like Medify](https://medifyair.com/collections/air-purifiers/products/medify-ma-40?variant=39663322628163).

The best? Really? You really want the best? Here you go: https://aghealth.ucdavis.edu/news/corsi-rosenthal-box-diy-box-fan-air-filter-covid-19-and-wildfire-smoke this is the absolute best air purifier, backed by science. And cheap too. I have one too.