Triple Exhalaron (3-fan)

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.

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.