The short answer
If the room is damp (above about 55 to 60 percent), a dehumidifier comes first: it removes the moisture mold needs. An air purifier with a true HEPA filter then catches airborne spores; it can't stop growth on damp surfaces.
How mold grows
Mold spores are everywhere. They grow wherever surfaces stay damp: cool basement walls, bathroom ceilings, behind furniture on exterior walls. Remove the moisture and growth stops.
What each does
| Dehumidifier | Air purifier | |
|---|---|---|
| Stops new growth | Yes, by drying the air | No |
| Removes airborne spores | No | Yes (HEPA) |
| Musty smell | Reduces it at the source | Carbon stage reduces it while running |
| Best for | Basements, crawlspaces, damp rooms | Allergy relief in a dry room |
Visible mold
Clean small areas on hard surfaces and fix the moisture source. Large areas, mold inside walls or after flooding are jobs for professionals.
SafetyWear gloves and an N95 respirator when cleaning mold, and keep people with asthma or weakened immune systems away.
Products mentioned
Questions readers ask
Will an air purifier get rid of mold?
It removes airborne spores but can't stop mold growing on damp surfaces.
What humidity stops mold?
Keeping relative humidity below about 50 percent limits mold growth.