Humidifiers can ease problems caused by dry air. Dry sinuses, bloody noses and cracked lips — humidifiers can help soothe these familiar problems caused by dry indoor air. Humidifiers can also help ease symptoms of a cold or another respiratory condition. But be cautious, they need regular maintenance. Although useful, humidifiers can become a household health hazard and actually make you sick if they aren’t maintained properly or if humidity levels stay too high.