Humidifiers: How to Choose the Right One

• Cool-mist humidifiers do their job by releasing a spray of cool mist into the air. Ultrasonic humidifiers, which use high-frequency vibrations to break up water into fine particles, are a type of cool-mist unit.
• Warm-mist humidifiers emit a mist of warm water, generated when the unit boils water then cools it a bit before it is released.
• Vaporizers boil water and send it in the air as steam, rather than mist.

Dr. Gordon recommends that parents of children in his practice use cool-mist humidifiers to help clear their little one's stuffy nasal passages. "If the temperature is 55 to 58 degrees, and the air is cool and moist, the mucous membranes work better. The cooler and moister your baby's room, the better."

He understands that parents often hesitate to put a chill in a sick child's room, but he assures them that the cool air is really the healthiest. "Parents use warm-mist humidifiers because it makes them feel better," he says. "But being cold does not make you sick."

The benefit of warm-mist humidifiers and vaporizers is that when they boil the water, they kill any bacteria that may be swimming in the water. The boiling process reduces—but does not eliminate—the need to clean the unit daily.