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Best humidifiers 2019: Keep the humidity perfect in your home

If your home or a room within it is consistently dry and cold when it shouldn't be, you might be looking at getting a humidifier to help you control the moisture levels. Just like a damp home can create mold and damage walls, a home that's much drier than its environment can fall victim to similar problems. It could even have an effect on your family's health, so a humidifier may well be a good purchase for you.

In addition to helping keep your family healthy, a humidifier can benefit your house and the objects in it. For example, it can make for healthier plants. Dry air can shrivel plants, and humidified air helps to moisten the soil. With the additional water in the air, plants thrive and stay healthy much longer.

Moist air can also reduce static electricity, so you’re less likely to get an annoying little shock when you pick up a wool blanket or brush by people or pets. Humid air also creates more warmth during winter months than dry air, which can potentially save you money on utility bills.

Humidifiers can even help your home itself since wood has a tendency to shrink and split in dry air. As such, even wood floors and furniture can benefit from the moisture.

But which humidifier is the best one for your needs? That will depend on the size of your room size, of course, as well as your preferences for technology, comfort features and how hard you need your humidifier to work.

We've evaluated dozens of humidifiers from various different manufacturers to find the best one for you. With useful features like an automatic shut-off, both cool and warm mists, and a mineral removal filter, the Boneco 7135 is our top choice. This lightweight, ultrasonic model diffuses 3.5 gallons of water into the air per day, humidifying an area up to 650 square feet.

1. Boneco 7135: Best overall

Boneco 7135

Boneco 7135

Dimensions (L x W x H): 15.2 x 8.8 x 15.4in | Weight: 8lb | Mist: Warm, cool | Max room size: 650 sq ft | Humidity output pr 24 hours: 3.5gal | Water tank: 1.75gal | System: Ultrasonic

Highest water output per day
Large water tank
Programmable humidistat
Second-most expensive unit
Needs pure water for best performance
Warm mist setting has scalding risk

The Boneco 7135 is an ultrasonic humidifier that can turn up to 3.5 gallons of water into a fine mist each day, treating rooms up to 650 square feet.

Not only is it quiet, but it also has warm- and cool-mist modes, though the warm mist mode can pose a scalding risk in children's bedrooms. The 1.75-gallon water tank is the second largest we reviewed and only needs to be refilled twice a day to keep up with the Boneco's maximum water output.

As with all ultrasonic humidifiers, using pure, demineralized water is important to avoid spreading bacteria and mineral dust. If you have hard water, the Boneco's included demineralization cartridge can improve performance. This humidifier also has a specialized cartridge to help prevent mold and bacteria growth in the tank. In addition, it has a helpful indicator light on the control panel to remind you when it needs cleaning.

There are many useful features built into this Boneco model, including a humidistat, timer and sleep mode, that let you customize how your machine runs and how humid your room is. Because it has so many features, this humidifier the second-most expensive model we looked at, but Boneco covers the 7135 with a three-year warranty.

2. Honeywell HCM-350: Best value

Honeywell HCM-350

Honeywell HCM-350

Dimensions (L x W x H): 18.6 x 10.4 x 13in | Weight: 9.5lb | Mist: Cool | Max room size: 500 sq ft | Humidity output pr 24 hours: 2.3gal | Water tank: 1.1gal | System: Evaporative

Very affordable
Three-year warranty
Good water output per day
No timer or humidistat
No auto shut-off
Wick adds to long-term costs

The Honeywell HCM-350 is an excellent value for many reasons, particularly if you don't need extra features. This cool-mist humidifier can treat rooms up to 500 square feet and has a water output of 2.3 gallons per day.

The water tank holds 1.5 gallons, which is more than other budget humidifiers that often hold a gallon or less.

Because this is an evaporative humidifier, it creates moisture by blowing air through a water-soaked wick. The wick has antibacterial properties and helps capture minerals before they get into the air. 

It also has an ultraviolet light between the water tank and the wick that can kill bacteria for an added layer of purification. However, you need to change the wick out every so often, as it becomes less-absorbent and effective over time. 

Replacement wicks cost around $10, so this can make the machine more expensive in the long run than some ultrasonic models.

The Honeywell HCM-350 doesn't have many convenience features like timers, humidistats or an automatic shut-off. This means you need to keep track of the machine while in use so it doesn’t run out of water, which could lead to overheating. 

This humidifier has three fan speeds, which don't produce much noise but allow you to adjust the water output. The three-year warranty on the Honeywell HCM-350 is much better than the one-year coverage you get on similar-priced humidifiers.

3. PureGuardian H5225: Largest water tank

PureGuardian H5225

PureGuardian H5225

Dimensions (L x W x H): 10.3 x 12.4 x 13.5in | Weight: 6.45lb | Mist: Warm, cool | Max room size: 650 sq ft | Humidity output pr 24 hours: 2gal | Water tank: 2gal | System: Ultrasonic

Large water tank
Includes a tray for essential oils
Humidifies rooms up to 650 sq ft
No humidistat
Needs pure water for best performance
Placing essential oils in the tank can void warranty

At 2 gallons, the PureGuardian H5225's water tank is the largest of the humidifiers we reviewed and is easy to fill in most kitchen sinks.

That means you won’t need to refill this humidifier as much as other models. The PureGuardian can treat the air in medium to large rooms. This unit has both warm- and cool-mist settings, so you can choose what’s best for you. 

This humidifier is designed to use with essential oils. You simply put the oil on the oil tray in the back of the unit. You should never put essential oils in the tank as this can damage the humidifier and void the warranty. 

You can set the humidifier to shut off after 2, 4 or 8 hours and it will automatically shut off when it runs out of water, preventing damage to the ultrasonic misting element. 

Unlike some other models we looked at, the H5225 doesn't have a humidistat. It is advisable to purchase a separate humidistat so you can keep humidity at safe levels. 

It also lacks a demineralization filter. It’s always a good idea to use purified water, but this is especially true if you live in a hard water area. On the plus side, it has a split nozzle to spray mist in different directions. 

Although the PureGuardian H5225's three-year warranty isn't the longest we've seen in a humidifier, it's competitive with many other brands.

4. Vornado Evap2: Best evaporative humidifier

Vornado Evap2

Vornado Evap2

Dimensions (L x W x H): 8.8 x 9.5 x 14.1in | Weight: 6.1lb | Mist: Cool | Max room size: 600 sq ft | Humidity output pr 24 hours: 2gal | Water tank: 1gal | System: Evaporative

Doesn't leave fine white dust behind
Cool-mist only

Humidifiers use either ultrasonic or evaporative technology to create a humidifying mist. Both have advantages and disadvantages. For those who prefer the evaporative humidifiers, the Vornado Evap2 is the best option. 

At a coverage level of covers 600 square feet, it's perfect for a medium sized room. And it only requires one refill per day, as it has a one-gallon reservoir and runs 2 gallons per day. 

Since it’s evaporative, it doesn't leave behind the white dust common with ultrasonic humidifiers. It's also safe to set on hardwood surfaces, as it doesn't leave damp spots. 

However, it's also louder and uses more energy than an ultrasonic model. Many people find the louder sound of a humidifier fan comforting, as it functions similar to a white noise machine when sleeping.

The Vornado only produces a cool mist, as it lacks a heating element for a warm mist. The best humidifiers function as both, making them versatile in warm and cold climates. If you have kids, especially small children, a cold-mist humidifier like the Vornado is the safer option, as it can't scald them with steam or hot water.

5. Holmes HM2610: Most affordable ultrasonic humidifier

Holmes HM2610

Holmes HM2610

Dimensions (L x W x H): 10 x 10 x 14in | Weight: 5lb | Mist: Warm, cool | Max room size: 600 sq ft | Humidity output pr 24 hours: 2gal | Water tank: 1.5gal | System: Ultrasonic

Very quiet
Leaves white dust behind

Ultrasonic humidifiers are popular because they are very quiet and efficient. However, these humidifiers are more expensive than evaporative models. At about $50, the Holmes HM2610 is most affordable ultrasonic humidifier we tested. 

It's not as quiet as more expensive ultrasonic humidifiers, but it's much quieter than evaporative models. It produces just a small hum with the occasional gurgle as the water moves through the system. 

It doesn't have the coverage area of more expensive humidifiers, but it's still plenty capable, covering 500 square feet with 2 gallons per day. It also has a large 1.5-gallon reservoir for a humidifier at this price, and it runs uninterrupted for 24 hours, for less refilling.

The downside to an ultrasonic humidifier like the Holmes, is the white dust it leaves behind if the humidifier isn't fitted with a filter to remove the minerals from the water before it's turned into a mist.

Why trust us?

Top Ten Reviews has reviewed humidifiers since 2012 and began in-house humidifier testing in 2015. As we test, we hold ourselves to precise standards, mainly centering on effectiveness and convenience. We work to ensure our tests match your expectations and not those of manufacturers. 

When researching humidifiers, we did extensive online research. We read professional articles that discussed humidifiers in terms of their technology, functionality and maintenance, and we found different humidifiers for specific types of users. 

We read dozens of user and professional reviews to get an idea of problems people experience and to understand the best way to use and maintain them. We also talked to manufacturers and professionals to increase our own knowledge and better help our readers.

An article on the Mayo Clinic website says that if your child has asthma or allergies you should talk to a doctor before using a humidifier. This is an opinion shared by a professional we spoke to, Michele Cassalia, Director of Marketing for the Asthma and Allergy Foundation of America

We also spoke to Karen Boren, a writer who has done extensive research on health and wellness and has been published on sites like PubMed. These experts provided invaluable information about the best ways to use humidifiers so you can maximize the benefits and reduce or eliminate potential threats. The following sections contain information and quotes from our conversations with them.

Cassalia emphasized the importance of daily maintenance of your humidifier, regardless of the brand or type. While there are a lot of humidifier options out there, the AAFA only certifies the Dyson humidifier. We discuss this in detail in the section below on the latest technology. 

Cassalia said humidifiers can be tricky and the number one rule with them is you need to check with an allergist, immunologist, pediatrician or a general doctor to see if the humidifier is going to help you and your sinuses survive winter. “This is especially true if you have in-door allergies to mold or dust mites,” she said. “Always check with a doctor.”

How much do humidifiers cost?

There are many types of humidifiers with a wide range of prices, typically determined by the coverage area the humidifier is designed for. Here is a breakdown of the most common types of humidifiers:

  • The most common humidifiers, whether evaporative or ultrasonic, cost between $20 and $150. The more expensive models are designed for large rooms.
  • The most affordable humidifiers cost under $10. These are typically very small, cool-mist humidifiers designed for baby nurseries or for an office desk. The coverage area is between 10 and 20 square feet.
  • The most expensive humidifiers cost between $3,000 and $6,000. These humidifiers are more comparable to AC units than the single-room humidifiers we reviewed. These are large appliances installed outside, and use your home's central air system to humidify the entire home. They are common in homes with high-end hardwood floors, which require a specific level of humidity to keep from warping. 
  • Oil diffusing humidifiers cost between $30 to $80. These humidifiers combine essential oils or fragrances with the mist, used mostly for homeopathic health reasons.

How to maintain your humidifier

A humidifier's effectiveness relies heavily on how well it is maintained. It’s vital to keep your humidifier clean. A dirty humidifier can be a health hazard, spewing bacteria and fungi into the air that can lead to a variety of problems ranging from heightened allergies to serious lung inflammation. 

An article on Time.com talked about a case study that involved a baby who developed a serious lung injury from breathing in the powdery buildup of metal deposits on the inside of a humidifier’s reservoir.

Just be sure to avoid cleaning your humidifier with harsh chemicals. The Evaporative vs. Ultrasonic section above provides information about cleaning those specific types of humidifiers. If you want to put a humidifier in your baby’s room, Sweet Mom’s Blog has helpful information specific to buying and using the right humidifier for your baby, along with pros and cons for each product, some related to maintenance.

Michele Cassalia, the director of marketing for the Asthma and Allergy Foundation of America, said what often happens is a person will go away and leave a humidifier sitting for a couple days. The water collects dust and mold, and if you turn it on, it spews all of that into the air. Cassalia strongly recommended emptying out the reservoir and washing it out with hot soapy water every day, then filling it up with distilled water from the store to avoid impurities from tap water. She also recommended cleaning it out with white vinegar once a week. “Allow the machine to run 30 minutes in a well-vented area, like a garage or outside, and let it run through 2 cups of white vinegar,” she said.

How we tested humidifiers

Our scores don’t rely exclusively on manufacturer specifications; we also look at the aspects most important to you like how loud and how bright the humidifier is.

For our sound tests, we set up each humidifier in a bedroom overnight. We measured the sound output using a decibel meter and didn't find any major differences between the units. In fact, we consider each unit we reviewed quiet enough to put in a bedroom without interrupting sleep. 

Our light tests were more subjective, looking at whether each humidifier put out too much light from across the room. Our results were similar to sound testing because there were few differences between the units and none of them caused our light-sleeping tester to stay awake.

While these are minor details, they can affect your sleep quality if you're sensitive to sound and light. We made note of these items in each product's reviews where appropriate but ultimately decided not to include them in our scoring for now. We are constantly re-evaluating our testing methodology each time we update this review and hope to expand it to be more useful to you in future updates.

How to find the best humidifier for your baby

The best humidifier for your baby is similar to a humidifier you would buy for yourself or older children. However, its functionality and quirks are even more important when you place it in your baby’s room. You want a humidifier that can run quietly all night. It should also be easy to use and maintain, and it should work effectively.

There is a whole line of humidifiers designed to look like cows, penguins and other adorable creatures to fit the decor in a baby's room. Such humidifiers, to the degree that you keep them clean and well maintained, serve their purpose and perform adequately. 

However, most humidifiers designed specifically for babies are ultrasonic, which can create too much moisture, sometimes to the point of puddling. Because of the excess moisture, ultrasonic humidifiers are also more susceptible to white dust, a powdery buildup of metal deposits on the reservoir, which can spew dangerous toxins into the air. 

One of the best humidifiers for your baby’s room is our best value pick, the Honeywell HCM-350B. Customer reviews for the Honeywell humidifier are generally very positive. It comes apart easily and is easy to use and clean; in fact, all of its parts can be cleaned in the dishwasher. It is bigger and more solidly built than most of the animal-themed baby humidifiers out there. And a toddler is less likely to try to play with it and knock it off a dresser when they get big enough to reach it from their crib. 

This Honeywell model is evaporative, not ultrasonic. It uses a patented process that Honeywell claims kills 99.9 percent of all germs. Further, it is quiet and has a big water tank that can last for 12 to 16 hours, and it covers a humidification area of about 500 square feet. It also produces a cool mist that is ideal for babies and small children because there is no hot steam or hot water that could potentially scald them if the humidifier accidentally tips over.

Humidifier types: Is warm mist or cool mist better?

Some humidifiers offer both cold and warm mist outputs. The ones that provide warm mist move the water over a heating element. While warm mist usually leaves an ultrasonic humidifier at a safe 104 degrees Fahrenheit, a curious child could tip over the unit and get burned by the water inside. To be safe, use cool mist humidifiers around children or infants.

Warm mist humidifiers are generally considered to be healthier because they can fight off bacteria and mold better than cool mist humidifiers. The two types of warm mist humidifiers are steam and vaporizers. They are good for use during winter because they help warm the air. Warm mist humidifiers are typically quieter and have more options in portable sizes.

Cool mist humidifiers are a better choice if you have children, because you won’t have to worry about the humidifier getting knocked off a countertop and scalding a child with dangerously hot water. Cool mist humidifiers require less electricity than warm mist humidifiers. With both types of humidifiers it’s important to keep them well-cleaned, but cool mist humidifiers should be cleaned even more frequently and thoroughly, since they are less prone to killing built-up bacteria and mold than warm mist humidifiers. The two types of cool mist humidifiers are ultrasonic and evaporative. Ultrasonic humidifiers are quieter than most evaporative models and some ultrasonic humidifiers have warm mist features. 

What kind of water is safe to use in a humidifier?

It’s not uncommon for people to use regular tap water in humidifiers, but this is not the best option. If you are going to use tap water, make sure it is filtered. Some humidifier manufacturers suggest using distilled water; others recommend using demineralization cartridges or filters. The user manual or the company’s website should contain these types of details for your specific model.

The Mayo Clinic recommends using distilled or demineralized water. A Mayo Clinic article on humidifiers says, “Tap water contains minerals that can create deposits inside your humidifier that promote bacterial growth.” According to the article, you can breathe these minerals when they’re released into the air, and they often appear as white dust on your furniture.

With lower mineral content than tap water, distilled or demineralized water is less likely to promote bacterial growth. You can also discourage the growth of bacteria by regularly cleaning out the humidifier with dish soap and distilled or filtered water. Also, hard water or water high in mineral content is tougher on your humidifier and will cause it to wear out faster than it normally would.

Can you put essential oils in a humidifier?

Different sources provide contradictory advice in answer to this question. Some say you should only use essential oils in warm mist humidifiers and others say the opposite, to only use them in cool mist humidifiers. 

We spoke to Karen Boren, a professional writer and editor who has researched and written extensively about essential oils. She said humidifiers work the same way as diffusers. Some oils can melt plastic, but you can avoid this by putting the oil in water first, she said.

As this blog states you can use essential oils in some cool mist humidifiers. If the humidifier is compatible with essential oils, it will say so in the humidifier’s insert, so consult that before trying it. 

Like diffusers, humidifiers designed for this break down the essential oils in water to create a fine mist that will spread the aroma throughout the room. This can potentially have health benefits that include allergy reduction, headache relief and a boosting of the immune system among other things.

Can a humidifier be good for your skin?

Humidifiers are potentially good for many issues common in dry climates, like allergies, asthma, coughing, colds and dry and itchy skin. Theoretically, if you have enough moisture in the air it could even eliminate wrinkles, but that would require more than a comfortable amount of moisture, and too much moisture is also unhealthy.

According to the Mayo Clinic a healthy humidity level is 30 to 50 percent. The Asthma and Allergy Foundation of America puts an even narrower margin on healthy humidity levels. Michele Cassalia, director of marketing at the AAFA, said you should keep humidity levels between 40 and 50 percent. 

She suggested it is a good idea to invest in a hygrometer to measure the humidity in your house. Some humidifiers have hygrometers built in, but if not, it’s a good idea to purchase one. “That way you can turn off the machine if it gets past 50 percent,” Cassalia said.

If there is too much humidity in your home it can cause harmful bacteria and mold to grow. This can lead to some of the same problems as overly dry air, like respiratory problems and allergy and asthma flare-ups. But a well-maintained humidifier will keep the air hydrated just right. After a while you may find you don’t need to use as much lotion, but your skin will look and feel soft and supple.

Cassalia said humidifiers have come a long way in the last 25 years. She lives in the Northeast in an extremely dry area of the country. She said her son had severe asthma, eczema and food allergies, back when it was hard to find a good humidifier. 

She said a humidifier, used properly, can help with skin conditions like eczema, but you should always consult with a doctor before investing in one to decide if it’s a good choice for you and your family.

Humidifiers: Performance and design elements to look out for

When purchasing a humidifier, you should consider the room size it can effectively humidify and its method of mist dispersal. While a small model like the Avalon 2.8 Liter Cool Mist Humidifier is a very affordable option and works well for a small bedroom, it is not optimal for a room larger than 250 square feet. If you have a room much bigger than that, you will want a humidifier with a 1-gallon tank or bigger. This will be better equipped to provide a high output of mist for family rooms, dens and other large rooms.

Some older humidifiers, and even some more up-to-date ones, produce steam using a heating element which boils the water in a reservoir. This is not the safest design, especially if you have curious children or pets around. For this reason, we didn’t evaluate this kind of machine in our humidifier reviews and focused instead on the more modern and safer designs. We chose a selection of evaporative and ultrasonic humidifiers for our side-by-side comparison. For more information about these types of humidifiers, read Evaporative vs. Ultrasonic in our What to Look For section below.

Do humidifiers help reduce snoring?

Snoring can be caused by many factors, including allergies, upper respiratory illness, obesity, sleep position and drinking alcohol before bed. A humidifier can’t control for all of these factors, but by adding moisture to the air, a humidifier can reduce the dry mouth, sore throat, allergies and respiratory problems that often result from a dry climate. 

In helping you deal with these issues, a humidifier can indirectly help reduce snoring. Often snoring results from a combination of the factors listed above, so a humidifier may help reduce – though probably not alleviate – the problem.

Conversely, a humidifier that is not properly maintained can contribute to health problems, including allergies, by breeding mildew and mold. Cool mist humidifiers are especially susceptible to this, so you want to make sure you don’t worsen snoring, and other problems, by failing to properly maintain your humidifier. 

Can a humidifier make you sick?

According to the Mayo Clinic, the answer to this question is yes. As we’ve discussed in other sections, failing to properly clean and maintain your humidifier can lead to the formation of mold or bacteria, which can cause various health issues. 

Also, it’s important to monitor humidity levels and make sure they stay between 30 and 50 percent. Lower or higher than that can cause problems; low humidity can cause dry skin and irritated nasal passages, while high levels can lead to bacteria, dust mites and mold growth, which can cause respiratory problems and complicate allergies and asthma.

If you have asthma or allergies, a dirty humidifier can make these conditions worse, but even healthy people can potentially experience flu-like symptoms or lung infections if the mist or steam released by the humidifier is contaminated. 

The Mayo Clinic says steam vaporizers or evaporators may be less likely to release airborne allergens into the air than cool-mist humidifiers. It also recommends using distilled or demineralized water instead of tap water in a humidifier, since tap water can contain minerals. You should also clean it out every three days.  

Michele Cassalia of the Asthma and Allergy Foundation of America said what often happens is a person will use their humidifier and turn it off, then leave the house and forget about it. They come back a couple days later and turn it on again. “You’re defeating the whole purpose. The water’s collecting dust and mold and you’re putting that out into the air. 

So you want to make sure you clean it and use fresh water, distilled water. If you can’t afford distilled water use tap water of course, but at least clean it out every single day.” See the section above on maintaining your humidifier for more information on this topic.

Are humidifiers good for musical instruments?

Like furniture and floors, musical instruments made of wood greatly benefit from being stored in rooms with controlled humidity. Wooden instruments are usually built in temperature- and humidity-controlled environments – generally about 68 to 72 degrees Fahrenheit and between 40 and 55 percent humidity.

While instruments are made of many types of wood, all of it is hygroscopic, which means the wood contracts if it gets too dry and expands when it absorbs water. When the wood on a guitar gets too dry, the fretboard contracts. However, the fret ends stay firm and overhang the board, creating sharp edges. In extremely dry air, the surface of the guitar can cave in and the fretboard can sink, thus lowering the strings and creating a buzzing effect. In extreme cases, the bridge may even snap.  

A piano soundboard can crack if the air is too dry. Gaps can also form between wood pieces fastened together. One fairly common problem with pianos in dry climates is the hammers stick.

Also, wooden instruments don’t sound as good when subjected to too much dry air. If it’s important to control humidity when creating wooden instruments, it follows that it is important to store them in a humidity-controlled environment. Using a humidifier to keep the humidity at optimal levels can extend the life of your wooden instruments and help you get the best performance out of them. 

Are humidifiers good for pets?

Inflammation and infection can irritate your dog’s airways, leading to serious coughs. Increasing humidity to a safe level can help clear your dog’s airways and can improve or even cure a cough. 

Frequent sneezing, excessive hair loss, and recurring ear and skin infections are all signs of pet allergies as is your pet excessively biting or licking its paws. A humidifier can help with all these problems. By clearing your pet’s airways, moist air also improves asthma symptoms. 

Cat flu is a common, recurring ailment that causes symptoms like sneezing, runny eyes and runny nose. Increased humidity in the air improves this condition and can help your cat breathe easier by decreasing congestion.

However, too much humidity can cause other problems, such as fleas. As such, it’s important to not overuse your humidifier.

Standout features to look for in a humidifier

The best humidifiers on our lineup have built-in humidistats that measure the amount of moisture in the air. This helps you get the exact humidity level you want in your room instead of guessing at the unit's output. Digital displays can also help you set your air humidifier to the precise level you desire, and you can be sure the humidity levels are safe.

If your humidifier lacks a humidistat, you can still keep track of humidity levels and control them. Michele Cassalia of the Asthma and Allergy Foundation of America said if your doctor feels your health will be helped by a humidifier and gives you the go ahead, you should shop for one that has the features you need. The device should have a humidistat – or if not, you should buy a separate hygrometer to keep track of the moisture levels in your house. “That way you can turn off the machine if it gets past 50 percent,” she said.

Be sure to buy a humidifier that shuts off automatically when the tank runs out of water. This protects the motor from overheating and reduces the risk of electrical fire. If the unit you are looking to buy lacks an automatic shutoff feature, you should be sure that it has a transparent reservoir so you know when it needs to be filled.

The Heaven Fresh HF 710-B is a humidifier that disperses both cool and warm mist and holds up to 1.6 gallons of water. The digital display makes it easy to see the current humidity levels in the room, and you can adjust the dispersal level or turn it on or off from across the room using a convenient remote control. The clear panels on the side let you easily see the water level so you know when it’s time to refill. Cassalia also suggested the Dyson humidifier as a good choice for many people because of its germ-killing technology. We discuss this in more depth in the following section. 

Latest tech: The Dyson humidifier

Addressing the concern of unhygienic humidifiers, which can be dangerous to your health, Dyson has developed a humidifier that uses ultraviolet light to kill bacteria in water. Dyson claims that its humidifier is scientifically proven to hydrate air. While this humidifier is pricier than any of the ones we evaluated, it is one of the best, most effective humidifiers on the market. As such, we will consider it for later inclusion in our side-by-side comparison.

Michele Cassalia of the Asthma and Allergy Foundation of America said the Dyson is the only humidifier the AAFA has ever certified. “It has to go through a lot of rigorous scientific testing by a third party, and then it goes through a lot of checks and balances to earn that certification.”

She said the Dyson is scientifically proven to reduce your exposure to allergens, and it can also sanitize the inside of the machine during use. In this way it is able to reduce preexisting contaminants in the room. Cassalia acknowledged that the Dyson is more expensive than other humidifiers on the market, but you get what you pay for. You can go out and buy one for $35, but you’ll probably want to throw it out after a winter’s use, she said.

“The Dyson humidifier has a cleanse technology. It has a cycle that kills 99.9 percent of the bacteria in the water tank,” she said. You have to pay more initially for the Dyson, but it’s a humidifier you can keep around for a long time and it will effectively humidify the air. 

Experts meet to discuss air quality in hospitals

A recent health care symposium at Harvard University brought together professionals from a variety of backgrounds to discuss ways to improve patient outcomes through better indoor air quality in hospitals. A similar symposium is scheduled for May 2019, also at Harvard.

Leading academics, healthcare professionals, architects and engineers were among the attendees at the 2017 Harvard healthcare symposium. They sought to combine their expertise in planning and designing healthcare facilities to optimize health benefits for patients and staff.

Humidification was one of the primary ways they discussed to improve air in hospitals. Keeping humification at a healthy level can decrease the spread of airborne infections. Humidity also minimizes symptoms related to conditions like allergies and asthma, which worsen with overly dry air. Breathing more comfortably also leads to better rest.

Waiting rooms, intensive care units, X-ray facilities and surgery rooms have varying requirements for humidification and hydration. Keeping humidity in maternity and obstetric wards at safe levels is especially important because babies are sensitive to dry air, particularly those with respiratory problems.

In an online video from the 2017 symposium, Mari Netto, vice president of operations at Novaerus Inc. said, “The air is finally becoming an important topic, and understanding that we need to clean the bacteria and the viruses out of the air. I’m grateful that it’s becoming a topic that people are placing an emphasis on.”

Another attendee, Dr. Rahul Rastogi, M.D., chief operations officer at Northwest Permanente, said the symposium was a great venue for the convergence of multiple disciplines. He feels it is a fantastic time to innovate by bringing engineers into the healthcare realm. “We’re bound to do wonderful things together. I think more physicians would benefit from hearing these discussions, particularly those whose focus is in infection control and invention,” Rastogi said. “Bringing them into this environment might open their eyes to factors that aren’t necessarily considered routine standard practices.”

What to look for in a humidifier

Evaporative vs. ultrasonic:
Evaporative humidifiers use a filter that is in direct contact with the water in the reservoir tank. The water wicks up the filter, and the humidifier then blows air through this large, wet surface, dispersing mist into the room. The filter removes many impurities, but you need to regularly clean the humidifier and replace the filters so you are trapping, not spreading, germs and bacteria that can cause respiratory problems or mold growth.

Ultrasonic humidifiers work by using vibrations to turn water into a fine mist. They are lightweight, nearly silent and require very little electricity to run. However, they can produce a fine white dust that settles on your furniture and floors over time. While it's not required, using purified water or a demineralization cartridge to remove impurities in the water reduces this unwanted effect.

Coverage area & tank size:
The most important aspects to consider in a humidifier are the room size it can effectively humidify and its method of mist dispersal. While small models like the Avalon are affordable options for a small bedroom, they are not optimal for rooms over 250 square feet. Humidifiers with 1-gallon or larger tanks are better equipped to provide a high output of mist for family rooms, dens and other large rooms.

Design:
Humidifiers come in all shapes and sizes, but they share design aspects, such as a water reservoir, humidity controls and an output nozzle. The most effective cool-mist humidifiers also include a mineral removal filter that purifies hard water to eliminate bacteria and unwanted minerals before they are dispersed into the air.

If you have a specific place for your humidifier, check the dimensions to see if it's a good fit. The humidifier should be light enough to carry so you can place it where you need. It's also useful if the tank has handles that are easy to grip when the tank is wet and slippery.

Warranty & support:
All the humidifiers we reviewed come with at least a one-year warranty. The best manufacturers back their products for even longer – typically three years, though Vornado covers its products for an impressive five years. A solid warranty offers you peace of mind because you know the manufacturer will repair or replace defective parts.

ProductPriceOverall RatingPerformanceFeaturesDesignWarranty & SupportGerm-fighting TechnologyTank Size (gallons)Water Output (gallons per day)Ultrasonic or EvaporativeHumidification Area (square feet)Length (inches)Width (inches)Carry HandleMineral Removal FilterTransparent TankHeight (inches)Weight (pounds)Cool MistDigital DisplayTimerWarm MistHumidistatAuto Shut-OffWarrantyOnline ManualEmailPhone
Boneco 7135View Deal5/510109.86.51.753.5Ultrasonic6501011.413.77.73 Years
PureGuardian H5225View Deal4.5/59.89.3106.521.4Ultrasonic650815.611.55.63 Years
Winix AW600View Deal4.5/59.5107.56.51.33.17Evaporative60013.613.617.715.43 Years
Vornado Evap2View Deal4/58.86.89.51012Evaporative6008.86.1146.15 Years
Sunpentown SU-4010View Deal4/58.599.8312Ultrasonic50013.25.312.47.51 Year
Crane EE-8065View Deal4/598.38.331.22.5Ultrasonic50013.39.6$157.21 Year
Holmes HM2610View Deal4/59.37.8731.52Ultrasonic50011923.86.61 Year
Honeywell HCM-350View Deal4/5959.86.51.12.3Evaporative50013.210.418.69.93 Years