A humidifier is used to alleviate discomfort caused by dry skin, allergies, asthma and stuffy sinuses by increasing the moisture content (humidity) in the air. A warm mist humidifier heats water to produce steam that humidifies the air. A cool mist humidifier releases tiny water droplets into the air.
Comparison chart
 | Cool Mist Humidifier | Warm Mist Humidifier |
|---|---|---|
| Cost | Cheaper to operate | Heating element requires more energy |
| Operation | Noisier | Silent |
| Ease of use | Cleaning is easier | Cleaning is hard |
| Hazards | Suspended material such as microorganism and mineral in the water are diffused into the air by impeller and ultrasonic humidifiers. | Hot water and heating element may cause scalding. Risky with children around. |
Purpose
Both cool-mist and warm-mist humidifiers offer relief for allergies and asthma. If a person can breathe well in a sauna then a warm mist humidifier is suitable. If a person finds it difficult to breathe in a sauna then a cold mist humidifier is suitable.
In this video Dr. Ari Brown explains the uses of a humidifier in a baby’s room.
Types of Humidifiers
Types of Cool Mist Humidifiers
- Impeller humidifier – A rotating disc throws water on a diffuser which breaks water into fine droplets. The droplets exit as a cool fog mist.
- Ultrasonic humidifier – An ultrasonic diaphragm vibrating at very high frequency breaks down water into fine droplets which exit as a cool fog. This type of humidifier is silent.
- Wick/Evaporative humidifer – A wick is a filter that absorbs water from a reservoir. The wick provides larger surface area for the water to evaporate. A fan blows air to aid evaporation.
Types of Warm Mist Humidifiers
- Steam humidifier – It boils water and releases steam into the room. A medicated inhalant can be vaporized along with the water.
A buying guide for various types of humidifiers that outlines the symptoms, size and benefits:
Humidity levels
Humidifiers are required to maintain the moisture content of a room. 35 to 50% humidity level is considered to be healthy. A low humidity level results in dry and itchy skin or chapped lips. Humidity level greater than 50% results in growth of mold spores, bacteria and dust mites. 40% humidity is required for musical instruments to prevent their crazing or cracking of finish.
Optmimum humidity level for the flu virus
The flu virus thrives best when humidity is either over 98% or between zero and 50%. So Dr. Linsey Marr, a researcher at Virginia Tech, recommends keeping humidity levels around 50% (but not over 60%, because that can cause mold buildup) to give the flu virus the least chance of survival.[1]
Pros and Cons
Advantages of Cool Mist Humidifiers
- The absence of hot water or heating element eliminates the risk of injury and is safer to use with children around.
- The tank is easier to clean.
- The wick type humidifier is self-regulating as the evaporation from the wick is relative to the humidity level of the room.
Disadvantages of Cool Mist Humidifiers
- A fan is required to dispel the mist into the room and hence can be noisy.
- Any minerals, dust or microorganisms might be diffused along with the mist. The minerals diffused (mostly calcium) might settle on furniture and nearby objects and are difficult to remove. The dust and microorganisms can worsen the allergy or asthma. Hence it is advisable to use purified or distilled water.
Advantages of Warm Mist Humidifiers
- The minerals and dust in the water are not diffused along with the steam.
- Any medicated inhalant (such as Vicks) can be added to the water to be diffused into the room.
Disadvantages of Warm Mist Humidifiers
- The presence of heating element and boiling water pose a risk of scalding and could be dangerous with children around. There is also a risk of fire.
- Mineral deposits from hard water make cleaning harder.
- Bacteria thrive in the presence of warm water and hence require frequent cleaning.
- Heating element requires more energy to operate. This increases power consumption and operational cost.
Maintenance
All humidifiers require maintenance. Here are some steps you can take to keep a humidifier in good shape:
- Do not let water sit idle in the reservoir as this might lead to bacterial infection and mold formation. Clean the tank and filter regularly.
- Rinse the tank after cleaning to avoid harmful chemicals being released.
- Keep the area around the humidifier dry.
- Use distilled or demineralized water.
Price
Products on the list of best selling humidifiers on Amazon usually range from $30 to $80, with some high-end humidifiers priced at as much as $170.
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