A nagging cough that's worse indoors and at night is often an allergic reaction. Here's how an air purifier targets the allergens behind an allergy cough, what to look for, and the best models compared. ...

An air purifier helps with airborne mold spores and musty odor — but it can't remove mold on surfaces or fix the moisture behind it. Here's exactly where it helps, plus the best air purifiers for mold. ...

A HEPA air purifier is one of the simplest ways to cut indoor pollen during allergy season. Here's how HEPA handles pollen, the specs that matter, and the best models compared on pollen CADR, room size, and price. ...

Can an air purifier really protect your lungs? Here's how HEPA filtration helps, exactly what to look for, and the best air purifiers for lung health — compared on CADR, room size, noise, and price. ...