Why isnt an air filter effective against dust mites and mold?
Air filters are only effective on particles suspended in the air. The dust mite allergen is relatively large and dense compared to other particles, therefore, it does not stay airborne for a sufficient amount of time to travel a significant distance or through ductwork. Direct contact with these allergens in their breeding grounds is how individuals are exposed to them in the home, this is unaffected by air filtration devices.
