To help us provide you with free impartial advice, we may earn a commission if you buy through links on our site. Learn more

What Do Humidifiers Do?

What do humidifiers do - featured. A humidifier is working on a table as woman sits on a sofa in the background

Struggling with dry skin, throat and eyes? A humidifier may help

Depending on where you are and what time of year it is, you may find the air around you uncomfortably dry. If you’re finding that itchy skin, an irritated throat and dry eyes are becoming a problem, then it may be time to invest in a humidifier to alleviate your discomfort and make your environment healthier.

But while their benefits can be extensive, humidifiers aren’t suitable for everyone and all environments – and they should not be confused with dehumidifiers.

Read on to discover exactly how humidifiers work and whether purchasing this appliance is the way forward for your household.

What is a humidifier?

Humidifiers are indoor appliances that add moisture to an enclosed space by releasing fine water vapour into the surrounding air from a tank. They’re available in a range of sizes and may offer further features, too, such as measuring the humidity level in the air, releasing steam or cool mist, or an auto shut-off function.

Some humidifiers are built into your home’s air conditioner or heating system, but most are electrically powered portable machines that use steam or filtered vapour to mist a room.

Dr Jie Zhao is a research scientist specializing in indoor environmental quality and head of Delos Labs. He says is important to be aware of the different types of humidifiers: “Consumers should be aware of the differences – evaporative humidifiers, steam humidifiers and ultrasonic humidifiers – and their own needs, as certain kinds of humidifiers are better choices for people with respiratory issues.”

What is a dehumidifier?

As you may expect, dehumidifiers perform the opposite function to a humidifier and work to remove moisture from indoor air. They’re often used in conservatories, basements and other rooms in which damp might be a problem. They can help to improve air quality in these environments and prevent mold and mildew.

When should you use a humidifier?

Humidifiers are usually most useful in winter to combat the naturally dry air, which is then exacerbated by heating; but it really depends on your environment. If you suspect your home could benefit from a humidifier then you can test the humidity level with a hygrometer (around $20 at any home improvement store). Homes with less than 30% humidity could benefit from a humidifier.

Dr Zhao agrees: “Anyone living in a lower humidity environment or in a location with drier winter air can benefit from using a humidifier. People who suffer from allergies or respiratory issues may also benefit.”

What are the benefits of a humidifier?

Since humidifiers prevent dryness in the air, there are a range of benefits to be had, which will help to alleviate the following health issues:

– Dry skin
– Dry throat
– Dry, itchy eyes
– Chapped lips
– Poor sleep
– Snoring
– Allergies
– Respiratory problems
– Sinus congestion
– Asthma
– Nose bleeds
– Eczema

There are also a handful of household benefits to using a humidifier in a previously too-dry environment.

– Atmosphere feels warmer
– Beneficial for houseplants
– Prevents cracks in wood, plaster and leather

Are there any risks associated with using a humidifier?

Yes. If not maintained correctly, humidifiers can spread bacteria – which can become a health hazard. Check to see if your humidifier treats the water in its tank in any way before distributing it as vapour in your home.

Some models – the Dyson humidifier, for example – treat water using UV light before vaporizing, but others will need to be rigorously cleaned to ensure best hygiene. This is of utmost importance if using the appliance around babies, children or those with compromised immunity. “Be sure to replace the media filter regularly. Mold can grow on it and the material can also get less effective over time”, warns Dr Zhao.

Humidifiers can also cause allergic reactions and worsen respiratory problems if overused. As such, it’s important to check the humidity level in the air regularly, since too much humidity is just as problematic as not enough.

Dr Zhao advises opting for an evaporative or vaporizer humidifier to be on the safe side, saying: “Ultrasonic humidifiers create water droplets, which are essential particle matter made of water and any minerals or contaminants inside the water. We know that fine particulate matter is one of the most dangerous air pollutants in the world. Since people with asthma and allergies are more vulnerable, I’d recommend using evaporative or vaporiser humidifiers over ultrasonic ones.”

Note that excess humidity can also cause mold growth, which is harmful to our health and property.

In addition, steer clear of using warm mist vaporizers around children since there is a risk of causing burns.

Read more

In Depth