How to prevent white dust from forming in a humidifier

Humidifiers are essential in a home because they ease cold symptoms and other effects of dry indoor air. But have you noticed white dust or powder that spreads all over surfaces in your house after using a humidifier?

Ideally, a humidifier works by adding moisture to the air to prevent dryness that can cause body irritation. However, some humidifiers release a white mist in the air that turns into dust.

The dust can cause adverse health effects. This means you must figure out how to prevent it from forming.

You can prevent white dust from forming in a humidifier by using distilled water instead of tap water to humidify your home. Alternatively, you can either use a demineralization cartridge or switch to a warm or cool mist humidifier.

Read on to understand how the three methods work to prevent white dust from forming in a humidifier.

Why is there white dust in my humidifier?

White dust in a humidifier is a by-product of minerals found in water. During the humidification process, the minerals are released into the air in the form of mist.

As the vapor dries, the minerals transform into whitish dust. The dust then settles on surfaces and furniture.

white dust
Image: rosco23

White dust after humidification is common in homes that use impeller portable and ultrasonic humidifiers. These devices produce humidity through a steaming process.

Water in the reservoir is heated to form vapor which finds an escape route in the small openings of the humidifier. Once the mist is in the air, heavier minerals start falling down. They end up settling on surfaces around the house.

3 ways to prevent humidifier dust from forming

As mentioned earlier, you can prevent humidifier dust through several methods. We have covered each of them in detail.

1. Using distilled water

Humidifiers cause white dust due to the minerals in the water. This is because most homeowners fill their units with tap water, which has a high mineral count.

Some of the most common minerals include iron and sodium. To avoid this problem, consider using distilled water instead of tap water.

Distilled water will reduce white mist and dust significantly. It has a low mineral count and will not produce a white dust, unlike hard tap water.

Here is what to do:

  • Unplug the humidifier from the wall outlet.
  • Empty the tank if there is any tap water.
  • Clean the humidifier thoroughly. Ensure to follow manufacturer instructions on how to disassemble the unit and replace the filter.
  • Pour distilled or demineralized water into the tank.

Since distilled or demineralized water has a low mineral count, it will not cause any white mist or dust during humidification.

If you can’t access distilled water easily, we recommend that you get either the CO-Z or the Megahome countertop water distiller.

2. Using a demineralization cartridge

HoMedics demineralization cartridge
Image: HoMedics

A demineralization cartridge traps minerals in a humidifier before they become airborne. It prevents hard water build-up, filters mineral deposits, and purifies water.

The device can eliminate white dust containing calcium, lime, and magnesium.

Here is how to use a demineralization cartridge:

  • Buy a demineralization cartridge of your choice.
  • Add tap water to the humidifier tank.
  • Place the cartridge inside the water tank.

Depending on the type of cartridge you buy, you will have to screw it onto a humidifier tank and leave it to work.

If you’ve opted for this method, you may wonder which ones to buy. Here are the best demineralization cartridges for humidifiers.

1. HoMedics ultrasonic humidifier demineralization cartridge

The HoMedics ultrasonic humidifier demineralization cartridge works by banishing hard water build-up through ultrasonic filtration.

The device can reduce white dust containing magnesium, lime, and calcium caused by chemicals and minerals in hard water.

The cartridge also works as a water purifier. It will filter and purify hard water to ensure the humidifier mist is clean and functioning without contaminants. You can install it by dropping it into the humidifier tank.

You can get it online via Amazon.

2. Pure Guardian FLTDC20 humidifier demineralization filter

Pure Guardian FLTDC20 is a demineralization filter that is compatible with most humidifiers. It helps prevent releasing minerals or white dust into the air during humidification.

The best thing about this filter is that it is easy to install. You’ll only need to screw the filter onto a humidifier tank.

Once done, the filter will prevent the formation of white dust for up to 700 hours. If you want the best results, clean your humidifier tank first and always use fresh water for humidification.

You can get the Pure Guardian FLTDC20 online from here.

3. Elechomes SH8820/SH8830 humidifier filter

Elechimes SH8820/SH8830 is a universal water filter compatible with most brands of ultrasonic humidifiers.

It uses advanced water softening technology to purify the water in a humidifier tank and eliminates white dust. When in use, the Elechomes Humidifier Filter creates an ultra-fine mist that does not dry to dust.

How to prevent white dust using a warm or cool mist humidifier

Warm mist humidifier
Image: Sylvane

Not all humidifiers cause white mist or dust when humidifying a home. The culprits are ultrasonic and impeller units.

These devices aerosolize water and everything in it, including minerals and bacteria. Furthermore, they break down water molecules to fine mist using high-frequency vibrations, eventually causing white dust.

If your area has hard water, but you do not want to use demineralized water, consider purchasing a warm or cool mist humidifier.

Both cool and warm mist humidifiers are excellent options for adding soothing moisture to dry indoor air. You can also opt for a whole-house humidifier.

These appliances do not release any white dust into the air during humidification. However, they tend to be noisy. That is one reason people prefer ultrasonic humidifiers because they are quiet during operations.

Is humidifier white dust harmful?

For most homeowners, the white dust from a humidifier should not cause alarm. However, it can harm people suffering from allergies, asthma, and other respiratory conditions.

Furthermore, the risk can be significant if you do not maintain your humidifier. For example, any bacteria or mold in the device will shoot right into the air.

If you or your loved ones breathe the bacteria and it goes into the lungs, you will experience adverse health effects.


You can prevent white dust from forming in a humidifier in different ways. First, consider using distilled water instead of tap water.

Secondly, use a demineralization cartridge that will trap minerals in a humidifier before they become airborne.

If you are looking for a humidifier that does not leave white dust, consider purchasing a cool or warm mist humidifier.

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