Concern

• Mold grows in warm and moist environments such as under the kitchen sink, in basements and bathrooms. When a person uses a warm mist humidifier, he is adding excessive amounts of warm moisture to the air. If the humidity is too high in a room for too long, it can cause mold spores to form in the carpet, bedding and on the walls.
  
  

Mold Spore Allergy

• A person who is allergic to mold spores may be at greater risk when using a warm humidifier. Common mold allergy symptoms include irritated eyes, itchy throat, runny nose, sinus infections, nasal congestion and postnasal drip.
  
  

Mold Spore Complications

• People who are allergic to mold may experience extreme reactions to mold spores produced from warm humidifiers, including shortness of breath, wheezing and coughing, according to the Mayo Clinic. People who are not allergic to mold may experience complications such as mold induced asthma, a fungal sinus infection, a lung infection and inflammation of the lungs. If a person experiences any adverse reactions while using a warm humidifier, she should discontinue use immediately and talk with a doctor.
  
  

Prevention

• The Environmental Protection Agency states that mold spores from a warm humidifier can be prevented with daily maintenance and by following the manufacturer's cleaning instructions. The water basin should never be left on the unit when not in operation. All water should be emptied daily and left to air dry. The heating element should be cleaned by wiping it down with a damp cloth to remove any debris. Using filtered water or distilled water will also help prevent the growth of mold. The humidifier should be disinfected if any mold is visible.
  
  

Considerations

• Maintaining a dry space around the humidifier will help restrict the development of mold. Never place a warm humidifier within reach of pets or children because it can cause burns. Follow the directions of the manufacturer of the warm humidifier for proper safety and function.