Pros and Cons of Different Types of Portable (or Room) Humidifiers?

What Are the Pros and Cons of Different Types of Room Humidifiers?

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There are five general categories of portable room humidifiers available: cool mist, ultrasonic, evaporative, warm mist, and vaporizers. Each type offers pros and cons for users – evaluate the qualities of each to determine which best meets the needs of your family and home.

Cool mist humidifiers

Cool mist humidifiers emit a cool vapor to add moisture to the air. They utilize a filter that captures water impurities and are easy to clean. These humidifiers are ideal for use during warmer weather and in areas that experience a warmer climate.

Several benefits come with using a cool mist humidifier in a bedroom, office, or other living space in your home. They are the most popular style of humidifier, so there are numerous models from which to choose. Many types of mist humidifiers also take advantage of other technologies, such as ultrasonic and evaporative. Step number one is to understand the terminology.

Evaporative cool mist humidifiers

Evaporative cool mist humidifiers create an ultra-fine mist that’s released into the room. A fan inside the unit blows over a wick filter, allowing the room air to soak up the moisture and increase the humidity level.

Ultrasonic cool mist humidifiers

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Ultrasonic cool mist humidifiers rely on high-frequency vibration technology to dispense water droplets throughout the room. The vibration is silent and the moisture is expelled as a fine, cool mist.

Benefits of cool mist humidifiers

Cool mist humidifiers are a good fit for increasing the humidity level in larger spaces. These units are typically more effective than warm mist humidifiers at adjusting and maintaining the humidity level in bigger bedrooms, open living spaces, and common areas.

No heating element is used in a cool mist humidifier, which makes it a great option for a nursery or child’s room. Curious hands can avoid burn-related injuries when an evaporative or ultrasonic cool mist humidifier is used.

A couple of considerations to be aware of when purchasing this type of unit is the volume level and required maintenance. Because these devices rely on a fan to disperse the cool vapors, some units may produce more sounds than others. In addition, you’ll want to regularly clean or change (refer to your unit’s user guide for instructions) the wick filter to avoid the growth of mold and bacteria.


  • Emit cool vapor, safer for children and pets
  • Easy cleaning and little maintenance required
  • Filter out waterborne impurities
  • Can add inhalants, making them good for cold and flu sufferers
  • Cost effective
  • Helpful for asthma and allergy sufferers


  • Bacterial contamination can occur
  • Mineral dust may accumulate from water filtration
  • Operating noise

Ultrasonic Humidifiers

An ultrasonic humidifier employs a metallic diaphragm that vibrates at high frequencies to create water droplets that are added to the air. They use very little energy and have no operating noise, so they are great to use overnight and in areas where you don’t want to increase noise.

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  • Extremely energy efficient
  • No operating noise
  • No hot surfaces, eliminating burn risk
  • Easy to clean, little maintenance required
  • Good choice for asthma and allergy sufferers


  • Bacterial contamination may occur
  • Mineral dust accumulates
  • More expensive than other options

Evaporative Humidifiers

An evaporative humidifier operates much like a cool mist evaporator – it does not heat water to create humidity. It is a wick humidifier that uses a fan to circulate humidity. Because they do not generate heat, they are ideal for homes with children and pets.


  • No hot surfaces, safe for children and pets
  • Affordable
  • Easy cleaning, low maintenance
  • Good choice to treat asthma and allergies
  • Self-regulating


  • Operating noise from system fan
  • Bacterial contamination
  • Mineral dust accumulation

Warm Mist Humidifiers

On a cold winter day or when heavy congestion plagues your family, a warm mist humidifier offers cozy relief. Depending on the type of room where you want to boost humidity, a warm mist device may be a great option.

Warm mist humidifiers are often used to treat colds and the flu during colder months. They heat water to create vapor, which is cooled prior to being released. These systems are less likely to experience bacterial contamination because water is heated.

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Benefits of warm mist humidifier

Warm mist humidifiers offer healthier air that’s generally free of bacteria or mold spores because the water is boiled before the vapor is released. The harmful particles are killed before the mist leaves the device, making it a great option for homes in search of better indoor air quality.

Plus, if you’re looking for an exceptionally quiet humidifier, a warm mist device is a great choice. There is no internal fan, so the operation is virtually silent.

A warm mist humidifier is also ideal for relief from dry winter air. The mist creates a cozy environment, especially in smaller spaces.

Considerations for the humidifier that expels warm mist are the desired room’s size and cleaning process. Warm mist humidifiers work best in small to medium spaces. They’re less effective in large rooms. In addition, the boiling process can create mineral deposits, making routine cleaning a bit more difficult compared to cool mist units.


  • Reduced risk of bacterial contamination due to heat
  • Reduced mineral dust accumulation
  • Can add inhalants to treat colds and the flu
  • Quiet operation


  • Risk of burns, not suitable for use around children
  • Low energy efficiency
  • More difficult to clean

Vaporizer Humidifiers

A vaporizer may be either warm mist or cool mist. Inhalants can be added, making them a common choice to treat colds and the flu. They are typically quite affordable, making them a great choice for all budgets.


  • Bacterial contamination is less likely
  • Less mineral dust accumulation
  • Inhalants can be added to treat colds and the flu
  • Low operating noise


  • Heavy energy consumption
  • Burn risk
  • Harder to clean
  • Not for use near children