Mold and Moisture

• The Centers for Disease Control estimates that possibly over 300,000 kinds of mold exist, although the true number is unknown. They vary dramatically in their composition, but every single mold spore has one common characteristic: it must have a source of moisture to be able to grow. Mold spores cannot germinate without liquid, and so you will not find active mold in a dry environment. Mold spores exist everywhere, too small for the naked eye to see, but they become a problem only when they find a moisture source and begin to germinate.
  
  

Mold and Humidity

• Mold can grow beneath leaky plumbing, on flooded carpeting or on wet fabrics. But even if you have no leaks, floods or standing water, you can still develop mold if high humidity exists. Your home's risk of developing mold is extremely high if your indoor humidity level exceeds 70 percent, according to a North Dakota State University report. You can measure your humidity levels at all times by installing a humidistat, which looks like a thermometer but measures humidity.
  
  

Mold and Dehumidifiers

• A dehumidifier can neutralize the mold caused by humidity, and it can even remedy some mold caused by other types of moisture. For instance, if you have mold growth in a humid room, you can draw out the moisture with your dehumidifier and neutralize the mold (since it no longer has its essential moisture source). Also, if you have a damp surface such as a carpet or wooden fixture, you can use your dehumidifier to dry these surfaces as well, even if their moisture did not occur as a result of humidity.
  
  

Dehumidifier Limitations

• Although a dehumidifier can reduce the relative humidity in a room and aid in the drying of damp surfaces, it cannot evaporate standing water. If you have a flooded basement, for example, you need to remove the standing water using other means, such as a wet-dry vacuum, before you can use your dehumidifier to remove the remaining dampness.