Do Air Purifiers Really Work? And What Do They Actually Do?

Woman and her son setting up the intelligent home system on a smartphone. — Getty Images

As we head into the coldest months of the year, we may be asking ourselves how to minimize sickness while improving our overall air quality. After all, many of us are spending more time indoors right now, and the temperature doesn’t always make it ideal to crack open a window.

Enter air purifiers. There’s been a lot of debate over these devices, whether they actually work, and what they’re capable of doing. If you’re looking to clean the air in your home this winter but have some questions, read on for everything you need to know about air purifiers.

What Are Air Purifiers?

In theory, an air purifier does what its name suggests: it cleans the air. More specifically, it is intended to remove contaminants from the air in order to improve air quality and in some cases, odour. Often these devices are marketed towards people with allergies or asthma. But ever since the pandemic, more people have been using them to clear the air in their homes.

Do Air Purifiers Really Work?

The short answer is no, not on their own. However, a portable air purifier can help when it’s used in combination with other types of air purification. The best way to control air quality is to eliminate or control the sources of pollution. That means dusting and cleaning regularly.

It’s also important to ensure your home has proper ventilation by maintaining HVAC systems (remember to change filters regularly) and opening the windows when the temperature permits.

If you’re doing those things already, then an air cleaner with a HEPA (high-efficiency particulate air) filter can help further remove pollutants when used properly.

How Do Air Purifiers Work?

Air cleaners have a fan (or, in some cases, ions) that attract small particles in the air into a series of filters. Once they arrive at the filters, they’re pushed through until the particles are trapped and the “clean” air pushes through.

Are All Air Purifiers Created Equal?

No, they are not. These days there are all kinds of air cleaners on the market, but some may cause more harm than good. Ozone generators can produce indoor ozone levels at a hazardous level to your health, potentially harming cells in the lungs or respiratory airways. Exposure to ozone inflames the lining of the respiratory system and can cause symptoms like coughing, chest tightness, or shortness of breath.

Electric or ionized air purifiers can also be hazardous. They are designed to electrically charge particles in the air so that those particles stick to surfaces like walls or floors. But ozone is also released during that charging process, which can be worse for you than the unfiltered air was to begin with.

When looking for an air purifier, look for a HEPA filter designed to help get rid of allergens like dust, pollen, and certain bacteria. Some studies have shown that HEPA air purifiers can reduce particles in the air and help to improve allergy symptoms.

How Do I Choose The Proper Air Purifier?

There are a few things to consider when shopping for an air purifier. The type of filter is one of the most important considerations (skip ionizing or ozone generators in favour of one with a HEPA filter, such as this Dyson one). Then, look at how many square feet it covers, how much air it will draw through the filter, and what percentage efficiency rate it claims to have.

You may also want to look at the size and weight of the unit, along with how portable it is if you plan on moving it around your home.

What Won’t An Air Purifier Get Rid Of?

While many air purifiers may help clean the air in your home when used in conjunction with other purifying practices, air purifiers won’t really rid the home of gas or smells caused by gases, such as cooking smells.

They also won’t trap mold, nicotine, or larger allergens like dust and pollen, which typically settle on surfaces anyhow and are easy to wipe up.

What Are Some Other Ways to Keep the Air Clean in Your Home?

Aside from regular cleaning and ensuring you have functional ventilation in your home, there are a few other things you can do to minimize contaminants. Remember to clean fabrics and carpets on a regular basis, throw your bedding in the laundry every week (or two weeks if that’s too much), bathe your pets, and use nontoxic cleaning products.

It can also be helpful to keep your home between 40 to 60 per cent humidity, a level that has been shown to help prevent mold and dust.