What Is an Ultrasonic Humidifier

While the name ‘ultrasonic humidifier’ may sound like some kind of space machine, here we are actually dealing with a very useful device that is available to anyone.

Humidifiers in general are used to increase the amount of moisture in the air, and many people use them to improve their living conditions in case they are struggling with dry air.

Dry air is a common cause of dry lips and skin, and it can be the underlying reason behind experiencing stronger symptoms of congestion, flu, or the common cold, especially during wintertime.

There are two common types of humidifiers. Those that work with warm water and produce vapor by boiling hot water, called “warm mist” humidifiers, and those that simply work with cold water. These are usually called “cool mist” humidifiers.

Usually, cool mist humidifiers are considered a safer option, as they don’t require water heating, and among the ‘cool mist’ humidifiers, there are the ultrasonic and the evaporative ones. Learning more about these differences might help when selecting the best humidifier for you.

How Does an Ultrasonic Humidifier Work?

An ultrasonic humidifier has two parts: a water reservoir and a diaphragm made up of two ceramic plates. The diaphragm oscillates at a very high frequency, way beyond the human hearing spectrum.

These high oscillating vibrations are the reason why these humidifiers are called ultrasonic since the wavelengths being produced belong to the ultrasound part of the sound spectrum.

The vibrations send tiny, extra-fine droplets of water into the air which then evaporate, creating humidity in the room.

Unlike standard vaporizers and warm humidifiers, the ultrasonic humidifiers have no heating element, making them a much safer option for indoor use, as they simply work with cold water, which is why we call them “cool mist humidifiers”.

How Is an Ultrasonic Humidifier Different from an Evaporative One?

Evaporative humidifiers also fall into the ‘cool mist’ category, however, they operate quite differently. Their underlying mechanisms are the basic principles of evaporation that increase the humidity in the indoor air. This is basically similar to placing a bowl full of water into a room and leaving it to evaporate and make the room more humid.

However, these humidifiers speed up the process by using a fan and a wick filter that is placed at the base of the humidifier. The wick draws water up, and the fan blows on the wick, causing the water to disperse.

Ultrasonic units tend to be perceived as more aesthetically appealing, and many people prefer them over the evaporative models. The mechanism of an ultrasonic machine is far more compact and there are also very small units that are much easier to both find on the market and fit into your indoor environment.

The ultrasonic models are usually also enriched with some additional features such as LED lights that may come useful during the night or a built-in clock, which is a common feature that many people appreciate.

The Pitfalls of the Ultrasonic Humidifiers

One of the common pitfalls that worry some users of ultrasonic humidifiers, is that these units have no filters, and thus, may release and disperse contaminants such as minerals into the indoor air. Basically, whatever type of contaminant may be found in their tank, might end up in the air. The most common contaminants found in tap water are magnesium, calcium, potassium, and other minerals.

Once released into the air, these will probably end up as some kind of gray or white dust that settles on the floor or furniture. The amount of dust may vary depending on the amount of water used, but also on the hardness of the water. If you use hard water, it will probably yield more dust.

One of the things we can recommend is to use distilled water for air humidification.

You also need to clean your ultrasonic humidifier on a regular basis, to prevent various kinds of microorganisms and bacteria that breed in that environment.

On the other hand, evaporative humidifiers have filters, but these also require some special type of attention. For example, the filter needs to be cleaned and maintained on a regular basis, or in other cases replaced, and how often this will take place will depend on how often do you use it and how contaminated the water you use is. It is recommended to do it every one to three months.

Both types of humidifiers should be cleaned at least once every seven days, which should help remove any kind of leftover minerals and bacteria that might have developed there. You can use vinegar diluted in water or some other simple mixture for cleaning, however, make sure to read the instructions for your device.

Additional Advantages of an Ultrasonic Humidifier

When it comes to the levels of comfort with each of these units, the ultrasonic one is for sure more pleasant for the indoor environment, as it’s quieter. The ultrasonic unit works with high frequencies that the human ear can not detect, and thus, makes less noise.

If you want a humidifier that would be a good fit for the bedroom, the ultrasonic unit is for sure a more suitable option, as it won’t be disrupting your sleep with its noise.

When it comes to evaporative units, they may differ from each other in the levels of noise that they produce, however, there is no possibility to find a completely quiet one. Since the fans are constantly working, even the models that have a quieter fan will probably be louder than the ultrasonic unit.


If you are experiencing dry air in your indoor space, you may have noticed some issues with coughing, congestion, dry skin, and lips. To combat these unpleasant consequences or a lack of humidity in the air, it is recommended to start using a humidifier.

While there are several options available on the market, we strongly recommend an ultrasonic humidifier for several reasons:

  1. It’s quiet, doesn’t disturb your sleep;
  2. It looks appealing and often has some nice features like night lights or a clock;
  3. No filters to be replaced, just regular cleaning;
  4. With the use of distilled water, you can prevent the spreading of the contaminants that would otherwise be captured by the filter of an evaporative humidifier.