Table of ContentsView AllTable of ContentsWhat They DoTypesHow They WorkBenefitsEffectivenessAir QualityFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
What They Do
Types
How They Work
Benefits
Effectiveness
Air Quality
Frequently Asked Questions
Air purifiers are devices that filter air quality. They are helpful for people withallergies,asthma, and other respiratory or cardiovascular conditions. There are an overwhelming number of options, features, and brand names on the market, so it’s difficult to know not onlywhich one to pick, but if it’s worth picking one at all.
Air purifiers do work to filter pollutants from the air, but there are limitations to be aware of. In this article, you’ll learn about how air purifiers work, benefits, and factors to be aware of.
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What Does an Air Purifier Do?
On average, Americans spend 90% of their time indoors, and just like the outdoor world, there can be pollutants in your home.In fact, some of these pollutants are up to five times more concentrated indoors than outdoors due to:
The purpose of an air purifier is to filter these pollutants, chemicals, andallergensfrom the indoor air and improve air quality.
Types of Air Purifiers
HEPA Filters
HEPA stands for high efficiency particulate air filter. It is one of the most effective and studied air purifiers on the market.
It can capture extremely small particles of 0.3 microns or larger. Theoretically, HEPA filters can remove 99.97% of airborne dust, bacteria, mold, pollen, and other particles, although in reality its effectiveness will depend on factors like the age of the filter.
Research has shown that HEPA filters are highly effective at removing fungi, mold, and other allergens from indoor air.
HEPA Filters and COVID-19A HEPA filter or other air purifier alone isnotenough to protect you from viral infections such as COVID-19 infection.You should follow CDC guidance to prevent contracting or spreading viruses.
HEPA Filters and COVID-19
A HEPA filter or other air purifier alone isnotenough to protect you from viral infections such as COVID-19 infection.You should follow CDC guidance to prevent contracting or spreading viruses.
Ionic Air Purifiers
Ionic air purifiers tend to be less costly than HEPA filters, so people may opt for them for this reason.However, there are some important things to be aware of regarding their effectiveness and health impacts.
While this improves air quality, these particles remain, and may be recirculated to the air the next time you sweep, sit on the couch, lean on a wall, or walk across the floor.
Ion generators indirectly produce ozone, which is a lung irritant. The Environmental Protection Agency (EPA) notes that in some circumstances they can produce levels that negatively affect human health.
Many air purifiers work through a system of filtration to remove particles from the air and recirculate clean air. The exact mechanism of how this is done can differ between different brands and types of air purifiers.
The filter then traps particles above a certain size. This size will differ between air purifiers. For example, a HEPA filter is the highest standard and can trap particles greater than 0.3 microns in size.
Finally, the filtrated, clean air is then recirculated to the room through the fan. Over time, however, the filter will need to be replaced.
Some of the studied health benefits of air purifiers include:
Do They Work?
Yes, air purifiers do work, but with some caveats.
In reality, the benefits derived from air purifiers will depend on many factors, including:
How to Maximize the Benefits of an Air PurifierAir purifiers work best in combination with other cleaning techniques at home, such as:VacuumingSweepingMoppingCleaning out dustRegularly cleaning carpets, rugs, and soft furnishings
How to Maximize the Benefits of an Air Purifier
Air purifiers work best in combination with other cleaning techniques at home, such as:VacuumingSweepingMoppingCleaning out dustRegularly cleaning carpets, rugs, and soft furnishings
Air purifiers work best in combination with other cleaning techniques at home, such as:
Allergens
The term allergens refers to generally harmless substances that may trigger an allergic response in some people. Indoor airborne allergens can include:
Some air purifiers are effective at filtering allergens from the air. HEPA air purifiers, in particular, have been shown to be effective.
In one study, HEPA air purifiers significantly decreased allergen concentration (which was predominantly dust mites) in both the air and bedding.The participants, who all hadallergic rhinitis, also showed symptomatic improvement in nasal and eye symptoms and activity limitation.
Another study found that among schoolchildren with allergies, HEPA air purifiers were effective at reducing allergy symptoms of runny nose and inflammation.
Do Air Purifiers Help With Dust? Here’s What You Need to Know
Fungi and Mold
Fungi, which includes mold, mushrooms, and yeast, can be an allergen for many people. One study found that a HEPA air purifier fan was effective at reducing airborne fungi within homes.
Smoke
Smoke is a big concern regarding indoor air pollution. Smoke may be produced from:
One study found that portable HEPA filter air cleaners were effective at reducingsecondhand smokeexposure among non-smokers.
Another study among smoking households with non-smoking pregnant people found that while the HEPA air purifier reduced particulate matter in the air, it did not reduce air nicotine.Secondhand smoke exposure was reduced—but not eliminated—among the pregnant people. It did not change among the infants.
Ultimately, smoking cessation is highly preferred over the use of air purifiers. The United States Environmental Protection Agency (EPA) also recommends ventilating with clean outdoor air, if there is indoor smoking.
Indoor Toxins
How to Improve Air Quality at Home
You may choose topurchase an air purifierto help improve your indoor air quality. Here are some things you should look for as you choose the best air purifier for you:
It is recommended to use an air purifier in combination with other methods to manage your indoor air quality. Some other things to try to improve your indoor air quality include:
Summary
Air purifiers are effective at reducing the particulate matter in the air. Some types can lead to health benefits for those with allergies, asthma, and other conditions. However, there are many factors to consider when choosing the most effective air purifier. HEPA filters have the most research to support them and can filter extremely small particles.
A Word From Verywell
Most people spend the majority of their time inside, so indoor air quality can be a major concern. This is especially true for people with allergies or asthma, who may be reacting to airborne pollutants in their homes. Air purifiers can reduce these pollutants and help you feel better, but not all air purifiers are created equal. You should consider the type of air purifier, the size of the indoor space, MERV rating, and how often you’ll need to change the filter.
Ionic air purifiers emit large amounts of negative ions into the air. In the same way that static works, these ions attach to particles in the air (such as mold, allergens, and chemicals) and ground them. However, there can be negative health consequences to ionic air purifiers that negate their value as an air purifier.
The cost of air purifiers can vary greatly, from $50 to hundreds of dollars. You should also budget $50-$100 for annual filter replacement.
It is often recommended to run an air purifier for 12-24 hours a day. You should check the manufacturer guidelines. Additionally, frequently vacuuming and cleaning can improve the life of your air filter.
An air purifier draws pollutant particlesoutof the air, whereas a humidifieraddsmoisture particles to the air.
How long an air purifier lasts will depend on the particular brand, model, and level of air pollutants. However, many air purifiers last a full year before a filter must be replaced.
15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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United States Environmental Protection Agency.What is a HEPA filter?
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United States Environmental Protection Agency.What is radon?
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