Table of ContentsView AllTable of ContentsWhat Is a Humidifier?Cool Mist HumidifiersWarm Mist HumidifiersAsthma and AllergiesCombination Air PurifierChoosing the Right Size Humidifier
Table of ContentsView All
View All
Table of Contents
What Is a Humidifier?
Cool Mist Humidifiers
Warm Mist Humidifiers
Asthma and Allergies
Combination Air Purifier
Choosing the Right Size Humidifier
Many homes use a humidifier to make a room less dry, which some people find eases breathing related toasthma symptomsor otherrespiratory illnesses. It may also relieve dry skin. However, not all humidifiers are the same.
The two main types of humidifiers are cool mist and warm mist; among these products, there are different features available that make them better (or worse) for certain situations. Cool mist humidifiers include ultrasonic, impeller, and evaporative devices that use different technology to emit moisture. Warm mist humidifiers turn water into hot steam that is then released into the air.
This article explains the pros and cons of each type and offers suggestions on choosing one for your home or office.
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What Does a Humidifier Do?
Cool misthumidifiersand warm mist humidifiers both add moisture to the air. This moistens your skin (including your nasal passages) and thins mucus in yoursinuses. Using a humidifier can help relievecongestionfrom thecommon coldandflu.It can make it easier for you to breathe and breaks up mucus so it can drain.
To gain the benefits of using either type of humidifier, it’s essential to keep your device clean and properly maintained somoldand bacteria don’t build up in the humidifier. That could make you sicker.
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Cool mist humidifiers emit water that is room temperature into the air. There are three basic types of cool mist devices: ultrasonic, evaporative, and impeller. Each has different pros and cons.
A downside for all cool mist humidifiers is that you must carefully clean and maintain them to avoid a build-up of bacteria or mold.
Monitoring Your Home’s Humidity LevelsIt is helpful to monitor the humidity level in your home. The devices that do this are called hygrometers and are available at hardware stores for home use.The ideal humidity level in your home should be somewhere from 30% to 50%.Humidity levels higher than 60% encourage the growth of bacteria, mildew, mold, and fungi.
Monitoring Your Home’s Humidity Levels
It is helpful to monitor the humidity level in your home. The devices that do this are called hygrometers and are available at hardware stores for home use.The ideal humidity level in your home should be somewhere from 30% to 50%.Humidity levels higher than 60% encourage the growth of bacteria, mildew, mold, and fungi.
It is helpful to monitor the humidity level in your home. The devices that do this are called hygrometers and are available at hardware stores for home use.
The ideal humidity level in your home should be somewhere from 30% to 50%.Humidity levels higher than 60% encourage the growth of bacteria, mildew, mold, and fungi.
Ultrasonic
A reservoir of water is filled in an ultrasonic humidifier. Vibrations then help push microscopic droplets of water out into the air where it evaporates and moisturizes the room. Thus, these units are inexpensive and easy to use. They also tend to be quieter than other types of cool mist humidifiers.
Unfortunately, along with the water, any material in the water is released into the air. This may include minerals, bacteria, or mold.You can see the result as a fine white dust that may be left on furniture and material around the room after using an ultrasonic humidifier. This can cause harm to people with breathing problems. If you use chemicals to clean your device, there is a chance that residual chemicals could also end up in the air and be inhaled.
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Impeller
Impeller humidifiers use high-speed rotating disks to release water droplets into the air. The technology is simple, making it inexpensive, but it also means there is some mechanical noise associated with it.
Water passes through a filter before being released into the air. It’s important to clean the unit and the filter regularly to avoid impurities being emitted into the air.
Evaporative
An evaporative humidifier uses a fan to blow water through a filter and into the air. These filters are disposable, so you can replace them regularly to reduce bacteria and other materials from being released into the air.
Evaporative humidifiers are self-regulating, which means they will shut off when the desired humidity level is reached. Other cool mist units are more likely to oversaturate the air. However, the white noise emitted from these devices can irritate some people, especially when trying to sleep.
Reduce Impurities in the AirMineral deposits from hard tap water can be released into the air with cool mist humidifiers. These minerals can also damage the device. To reduce the risk, fill your humidifier withdistilled water, not tap water.
Reduce Impurities in the Air
Mineral deposits from hard tap water can be released into the air with cool mist humidifiers. These minerals can also damage the device. To reduce the risk, fill your humidifier withdistilled water, not tap water.
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Warm mist humidifiers heat water until it turns into steam and is then released into the air. This makes them less likely to emit water with bacteria or impurities and easier to clean. Warm mist humidifiers are usually less expensive than cool mist units and are often preferred during winter months.
While many people say that the heated water provides more immediate relief of congestion, there is evidence that shows that warm mist humidifiers actually cause swelling in the nasal passages, which can make it harder to breathe.This can make cold symptoms worse.
The major drawback for warm mist humidifiers, though, is that they pose a high risk for burns.
The American Academy of Pediatrics recommends against using warm mist humidifiers orsteam vaporizersif you have children because of the possibility of injury. It recommends the use of cool mist humidifiers only.
Dual HumidifierSome humidifiers combine the technology of a cool mist unit and a warm mist unit in one device, allowing you to choose which type of water vapor you want to use. These devices offer flexibility but need to be carefully cared for as well.
Dual Humidifier
Some humidifiers combine the technology of a cool mist unit and a warm mist unit in one device, allowing you to choose which type of water vapor you want to use. These devices offer flexibility but need to be carefully cared for as well.
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Humidifiers for Asthma and Allergies
Warm mist humidifiers tend to work well for easing symptoms like congestion that come with environmentalallergiesandasthma. However, there are concerns about using humidifiers because too much moisture in your home can increase dust mites.
Dust mites are a significant trigger for people with asthma and indoor allergies.Exposure can cause a mild to severe allergic reaction or an asthma attack.
If you do use a humidifier and have allergies or asthma, monitor the humidity level in your house carefully.
Humidifier Combined With Air Purifier
Air purifiers are effective at reducing certain irritants in the air and improving air quality. This can help with symptoms of the following:
A combined product should be designed to ensure that the HEPA filter does not get damp since moisture on a filter will make the purifier less effective.
Humidifiers come in a wide range of sizes. Some are small enough to fit in a cupholder and run on a USB plug. At the other end of the spectrum, whole-house humidifiers can cover more than 3,000 square feet.
The size of the water tank does not affect how much area a humidifier can cover. A larger tank is just a convenience, allowing you to refill the device less often.
Summary
The best humidifier for you and your home will depend on your needs. When you’re comparing cool mist humidifiers vs. warm mist humidifiers, you’ll find that while they have similar functions, each one offers its own benefits for managing certain health conditions or symptoms. No matter which humidifier you choose, make sure to read the directions and follow the instructions for safe use.
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Humidifiers and health.U.S. Consumer Product Safety Commission.Dirty humidifiers may cause health problems.Children’s Hospital Colorado.The hidden danger of humidifiers.U.S. Environmental Protection Agency.Mold course chapter 2: why and where mold grows.Lau CJ, Loebel Roson M, Klimchuk KM, Gautam T, Zhao B, Zhao R.Particulate matter emitted from ultrasonic humidifiers—chemical composition and implication to indoor air.Indoor Air. 2021;31(3):769-782. doi:10.1111/ina.12765U.S. Environmental Protection Agency.Use and care of home humidifiers.Food and Drug Administration.Use caution when giving cough and cold products to kids.Children’s Hospital of Philadelphia.Vaporizer or humidifier: which is best?Children’s Hospital Colorado.The hidden danger of humidifiers.American Lung Association.Dust mites.American Academy of Allergy, Asthma, & Immunology.Humidifiers and indoor allergies.Chen Renjie, Zhao Ang, Chen Honglei, et al.Cardiopulmonary benefits of reducing indoor particles of outdoor origin.Journal of the American College of Cardiology. 2015;65(21):2279-2287. doi:10.1016/j.jacc.2015.03.553
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Humidifiers and health.U.S. Consumer Product Safety Commission.Dirty humidifiers may cause health problems.Children’s Hospital Colorado.The hidden danger of humidifiers.U.S. Environmental Protection Agency.Mold course chapter 2: why and where mold grows.Lau CJ, Loebel Roson M, Klimchuk KM, Gautam T, Zhao B, Zhao R.Particulate matter emitted from ultrasonic humidifiers—chemical composition and implication to indoor air.Indoor Air. 2021;31(3):769-782. doi:10.1111/ina.12765U.S. Environmental Protection Agency.Use and care of home humidifiers.Food and Drug Administration.Use caution when giving cough and cold products to kids.Children’s Hospital of Philadelphia.Vaporizer or humidifier: which is best?Children’s Hospital Colorado.The hidden danger of humidifiers.American Lung Association.Dust mites.American Academy of Allergy, Asthma, & Immunology.Humidifiers and indoor allergies.Chen Renjie, Zhao Ang, Chen Honglei, et al.Cardiopulmonary benefits of reducing indoor particles of outdoor origin.Journal of the American College of Cardiology. 2015;65(21):2279-2287. doi:10.1016/j.jacc.2015.03.553
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
MedlinePlus.Humidifiers and health.U.S. Consumer Product Safety Commission.Dirty humidifiers may cause health problems.Children’s Hospital Colorado.The hidden danger of humidifiers.U.S. Environmental Protection Agency.Mold course chapter 2: why and where mold grows.Lau CJ, Loebel Roson M, Klimchuk KM, Gautam T, Zhao B, Zhao R.Particulate matter emitted from ultrasonic humidifiers—chemical composition and implication to indoor air.Indoor Air. 2021;31(3):769-782. doi:10.1111/ina.12765U.S. Environmental Protection Agency.Use and care of home humidifiers.Food and Drug Administration.Use caution when giving cough and cold products to kids.Children’s Hospital of Philadelphia.Vaporizer or humidifier: which is best?Children’s Hospital Colorado.The hidden danger of humidifiers.American Lung Association.Dust mites.American Academy of Allergy, Asthma, & Immunology.Humidifiers and indoor allergies.Chen Renjie, Zhao Ang, Chen Honglei, et al.Cardiopulmonary benefits of reducing indoor particles of outdoor origin.Journal of the American College of Cardiology. 2015;65(21):2279-2287. doi:10.1016/j.jacc.2015.03.553
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Chen Renjie, Zhao Ang, Chen Honglei, et al.Cardiopulmonary benefits of reducing indoor particles of outdoor origin.Journal of the American College of Cardiology. 2015;65(21):2279-2287. doi:10.1016/j.jacc.2015.03.553
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