Humidifiers can help with dry air issues. They do, however, require routine maintenance. Here are some suggestions to keep your humidifier from becoming a health danger. Humidifiers can help relieve dry sinuses, bloody noses, and chapped lips caused by dry indoor air. In addition, cool-mist humidifiers may help alleviate the symptoms of a cold or other respiratory disease. However, while essential, humidifiers can make you sick if not properly maintained or if humidity levels are too high. If you use a humidifier, make sure to maintain it clean and to monitor the humidity levels. Mold and germs can grow in dirty humidifiers. Before using a humidifier, see your doctor if you have allergies or asthma.