Why Does my Humidifier Have White Dust Around It?

Why does my humidifier have white dust around it?


The white dust that you often see around a humidifier comes from mineral deposits in the water used in the humidifier.

Hard water calcium deposits are often noticeable around your faucet and shower heads. Humidifiers that use the same water can also develop the same white calcium deposits.

The dust is not considered harmful but it can become airborne and inhaled.

  The high mineral content from the water can also be responsible for accelerated bacteria growth inside of the water basin of the humidifier.

How to clean the white dust off of your humidifier?

Hard water stain removal is an easy process that you can do with items that you generally have in your home already.

You will need a cloth towel, a bottle of apple cider vinegar, and some Dawn dish soap.

1. Completely soak the cloth towel with apple cider vinegar.
2. Cover the white calcium deposited areas on and around your humidifier with the vinegar soaked towel.
3. Allow it to sit for about 3 hours
4. Take the cloth off
5. Use the Dawn dishwashing soap to completely wash the area
6. Rinse the towel and wipe the area dry.

What can be done about the white dust that gets on your humidifier?



1.  Clean the humidifier more often

This step we have already gone through, but it cannot be stressed enough that a humidifier must be kept clean.

  Humidifiers can begin to grow bacteria inside of the water in as little as 48 hours. Operating a humidifier that has had standing water sitting in it can turn the device into a health hazard.

And water that has a lot of minerals in it can provide food sources for mold and bacteria to take root inside of the humidifier.

  Simply breathing and inhaling the mist from a dirty humidifier can result in illness and cause pneumonia-like symptoms.

  Legionnaires disease and Pontiac fever are serious conditions that occur from inhaling bacteria that has grown on water. Legionnaires can be deadly.

So stressing the importance of keeping your humidifier cleaner and done more often, not only helps keep the white dust away, it is honestly imperative that it is done.

2.  Switch the type of water 

The white dust deposits around your humidifier are there because of the high mineral content in your water.

Tap water and drinking water are full of minerals. Spring water even more so.

Even water that is processed by osmosis has minerals added back into it for consumption.

So what kind of water should you use in a humidifier?

A. Distilled water

The only water that is near perfect to use in a humidifier is distilled water.

It is because distilled water goes through a process that removes the minerals and particles from it.

Distilled water can even lengthen the life of your humidifier because  it eliminates the likelihood of mineral buildup inside of your machine. Build up that will eventually diminish the effectiveness of it.

B.  Boiled water

Boiling water will also separate the minerals of the water. If you have ever seen a pan that is used for boiling water over and over, then you probably noticed the white rings that develop on the pan.

If the pan is used specifically for boiling water, it will develop a layer of white calcium deposit that will eventually flake off.

But the main issue with using boiled water for the humidifier is filtering the clean part of the water into the humidifier without the big build ups of sediment getting into the humidifier with it.

Also it’s a huge ordeal to have to boil water every time you need to fill your humidifier.

( Notice we said boiled water and not boiling water, don’t pour boiling water into the humidifier. You will probably damage the humidifier beyond use and you will also risk getting burned badly in the process.)

C.  Filtered water

Water filters do not take out 100% of minerals and particles from tap water. But they do remove a huge portion of them. Using filtered water is better than using tap water but it is still not as good as using distilled water.

D.  Vaporizer/ warm mist humidifier

Warm mist humidifiers or vaporizers have a built-in advantage when it comes to keeping the water inside of the humidifier clean.

The advantage is the heat that they produce. Since these machines heat the water to a boiling point to produce steam, they also inadvertently kill bacteria and germs before they become an issue with your humidifier or your health.

Boiling water also separates minerals in water which are removed through the humidifiers filter.

Warm mist humidifiers have a lot of benefits and advantages over using cool mist humidifiers.

But they do have the downside of making a room feel steamy. Which can be great for a little while, but not so much when you’re trying to sleep. Especially if you’re sick.

They also have the danger element of containing scalding water. This is why every warning label you’ve ever seen about vaporizers says that they should not be used around or put in children’s rooms.



For most people, the prospect of purchasing gallons and gallons of distilled water for humidifier use will get less than an enthusiastic response.

  But cleaner water doesn’t just amount to just purchasing water that is already been treated.

There are products that you can purchase that will distill water for you, and or purify and filter your water.

And though some of these items may be more of an upfront cost, it is a cost that can end up saving you money in the long run.

1. Hard Water Filter

Hard water filters can be screwed right on to the end of a faucet or shower.

And if using the shower to fill your humidifier is an option for you, there is a much wider range of hard water filters you can purchase for the shower.

And since the shower head and the filter usually have the same size threads, you can easily put a filter on a shower.

More so than on a kitchen sink.

Hard water filters do not filter out 100% of all minerals from tap water but they do filter a majority of particles from the water.

And the price of one filter that can last you 6 months and even up to a year is a huge savings that will also help lengthen the life of your humidifier.

AquaBliss High Output Revitalizing Shower Filter

MULTI-STAGE sediment filters, redox media, calcium sulfite, activated carbon and ceramic beads deliver MAXIMUM WATER FILTRATION

2.  Home water distiller

Distilled water machines can be installed right on your kitchen counter.

These machines will distill up to six gallons of water per day. They not only remove minerals but completely eliminate any harmful chemicals that have been used to clean your water.

CO-Z 1 Gallon Water Distiller

This tabletop water purifier by CO-Z purifies water, filters out impurities, and dissolves VOCs at 0.3 gallons per hour

3.  Water purifier

You can take your water to a new level by purchasing a water purifier that will put your water through a vigorous four stage filter and reverse osmosis process with ultraviolet light.

Water purifiers can remove up to 99% of viruses bacterias and chemicals as well as heavy metals chlorine and fluoride.

Interested and having clean water available 24/7, not only for your humidifier, but having clean uncompromised drinking water, water purifying may be the way to go.

APEC Water Systems ROES-50 Essence Series Top Tier 5-Stage

Premium long-lasting filters remove up to 99% of contaminants such as chlorine, taste, odor, VOCs, as well as toxic fluoride, arsenic, lead, nitrates, heavy metals and 1000+ contaminants.

4. Demineralization cartridges

Demineralization cartridges are drop-in additives that you place into the water of an ultrasonic humidifier that binds particles together and causes them to stay on inside of the water tank.

  An excellent product for minimizing the amount of white dust that collects around a humidifier. But unfortunately they only work in ultrasonic humidifiers.

HoMedics Demineralization Cartridge for Ultrasonic Humidifiers

Eliminate Buildup: Ultrasonic humidifier demineralization cartridges help reduce the potential for white dust


What is the white dust that accumulates around my humidifier?



  The white dust that accumulates around a humidifier is mineral deposits.
It comes from tap water and more specifically, hard tap water.

Though it is not dangerous as far as being poisonous, it is capable of becoming airborne where it can be inhaled and cause a respiratory reaction.

The high mineral content in tap water can also Foster the growth of mold and bacteria faster in a humidifier water tank.

It is very easily cleaned. Apple cider vinegar is an excellent DIY product that you can soak a towel in and leave it on the hard water deposit stains.

After a couple of hours for 3, take the towel off and the stains will be virtually gone. Clean the rest with a little bit of Dawn dishwashing soap and water.

  One of the easiest things you can do to eliminate the problem of white dust and hard water deposits around your humidifier is to switch the type of water you are using.

Distilled water is the best for humidifiers because it goes through a process that eliminates the minerals from the water.

And though distilled water can get expensive there are ways to minimize the cost.

Home water distillers can be purchased and installed right on your kitchen counter.

One distiller can distill as much as 6 gallons of water a day. Plenty of water for a humidifier.

Purified water systems can eliminate 99% of all chemicals and minerals and create a system of safe water, not only for your humidifier, but for everyday drinking use.

Hard water filters are another product that you can attach to your shower head and remove most minerals and particles from your water.

Not on the same par as distilled water or purified water, still a great way to reduce the mineral content in your water for a small price.

Demineralization cartridges are also a disposable product that you can get as much as 6 months use out of that will help bind minerals together inside of your ultrasonic humidifier tank before they become a problem on the outside of your tank.

The biggest downside with these cartridges is that they only work with ultrasonic humidifiers.

The biggest thing you can do to minimize your exposure to any white dust or mold and bacteria that can form in your humidifier is to have a strict cleaning regimen for your humidifier.

Humidifiers can be very beneficial when used correctly. But when they are allowed to sit with standing water and then turned on, they can become a health hazard by emitting dangerous airborne bacteria into the air where it is inhaled.

Published by

Dennis Reed

Dennis Reed Owner and Author @