Humidifiers come in two primary types: Warm mist and cool mist. The Mayo Clinic notes that the mist is usually room temperature by the time it enters your lungs, no matter what temperature it was originally produced at, so there are other considerations when deciding between warm and cool mist humidifiers.
You may see cool mist humidifiers identified as evaporative humidifiers, impeller humidifiers or ultrasonic humidifiers. Warm mist humidifiers, on the other hand, may be identified as steam humidifiers or vaporizers.
Humidifiers, both those that put out cool mist and those that produce warm mist, re-hydrate your surroundings. This, in turn, can benefit everything from your immune system to wood furniture. If you suffer from chronic sinus problems, a humidifier might help. Likewise, if you suffer from allergies, a humidifier with a HEPA or other comparable air filter can help reduce dust and other allergens in your environment.
Warm mist humidifiers are typically quieter than non-ultrasonic cool mist humidifiers, but they cover a smaller surface area than comparable cool mist humidifiers.
The Mayo Clinic recommends using cool mist humidifiers around children, because hot water or steam from a warm mist humidifier might burn or scald a curious child who gets too close.
No matter what sort of humidifier you use, the Mayo Clinic recommends wiping it down daily with a 10 percent bleach solution. Dirt or mold can accumulate on evaporative humidifier wicks, algae can grow in the water tank, and the boiling water in warm mist humidifiers tends to leave hard-to-clean mineral deposits behind. White vinegar may help loosen these deposits. Always follow the manufacturer’s cleaning directions. A clean humidifier remains a health benefit for many, but a dirty humidifier can pose a health risk.
Cool mist humidifiers are generally less expensive than warm mist humidifiers. Most cool mist humidifiers cost $50 or less, and some warm mist humidifiers cost more than $100. Consumer Search warns that many of the bargain-priced humidifiers you’re likely to encounter are impeller models that must be filled with expensive distilled water, quickly evaporating your savings on the initial purchase price. Impeller humidifiers also tend to disperse microorganisms in the air and, if you try to skimp by using water that's not distilled, they disperse mineral deposits from the water as a powdery white dust. If you invest in a quality humidifier up front you may save money in the end, both on water costs and in health benefits.