Growing concerns about indoor air pollutants, from dust to smoke to viruses, have made air purifiers increasingly popular. And researchers have found everything from bacteria to carcinogenic compounds in household dust.
People with dust mite allergies and other sensitivities to airborne particles might be particularly interested in how an air purifier can help.
So how do they work? A fan-like mechanism draws air in and through at least one filter. The filter attracts and traps dust and other pollutants, thus cleaning your air. The filtered air is then released back into your space via another fan-like mechanism.
Some air purifiers are better at dust control than others, depending on the technology and filter system.
High-efficiency particulate air filters, known as HEPA filters, can remove 99.97% of dust particles that are 3 microns in diameter, according to the Environmental Protection Agency (EPA). As of now, air purifiers that have a HEPA filter tend to be the best at filtering out dust from your space.
Using air purifiers in smaller, enclosed spaces can also increase how effective they are.
Other filter technologies don’t work as well for dust filtration. For example, UV filters that zap mold spores and bacteria are also popular but aren’t as successful at trapping airborne dust. Some air purifiers take a “why not both?” approach and combine HEPA filters with UV filters or other types of filters.
All the air purifiers on our list use HEPA filters, except for the Molecule Air Mini+.
Clinical research: We read dozens of studies on dust filtration using air purifiers to figure out what works best in consumer and health services provider settings.
Type of filtration: None of these air purifiers are ionizers, which create a small amount of ozone. Instead, we focused on HEPA filters. In some cases, we highlighted products that combine HEPA with other filtration technologies. We also included an option with photoelectrochemical oxidation (PECO) technology.
Customer reviews and feedback: We looked through hundreds of reviews to determine what customers liked about these products, and to alert you of any red flags that you may want to consider before buying the product.
When you’re shopping for an air filter, there are a few things to keep in mind to make it easier:
Energy use: Some air filters are more energy efficient than others. Buying an air purifier that’s Energy Star certified isn’t just better for the environment, it’s better for your electric bill, too.
Filtration system: Different filters are meant to accomplish different goals. Purifiers that have a UV filter are great for killing viruses and bacteria but don’t filter dust as well as HEPA filters. Look into the filter technology before you buy.
Filter replacement cost: While you’re looking at the type of filter, check on what it’s going to cost to replace the filters and how often they are going to need a replacement. Some companies will void their warranty if you use anything besides their brand-name filters, so keep that in mind, too.
Space: Even the most powerful air purifiers will not be effective if they’re placed in a space that’s larger than their recommended capacity. Air purifiers typically market the maximum size room that they can handle efficiently, so don’t try to stretch it.
Noise concerns: As you research different products, take note of reviews that mention how loud the devices are. Some people like their air purifier on as a sort of white noise machine in the background as they sleep, while others need an air purifier that’s as silent as possible.
An air purifier can only effectively clean your home’s air when you’re using and maintaining it properly. These devices are made to last, but you can expect to do basic maintenance like changing the filter periodically.
Here’s what to keep in mind in terms of proper air purifier maintenance:
Read the owner’s manual: This will tell you everything you need to know about proper care for your specific air purifier model. You should also be able to find this information on the company’s website.
Position it properly: Make sure that your air purifier’s intakes aren’t blocked. Air needs to be able to circulate freely. Placing items on top of your air purifier could also obstruct air or cause damage. Unless it’s designed as a piece of furniture, do not treat it like one.
Replace filters as indicated: Your air purifier’s filters will need routine replacement, and this cannot be overlooked. If you use a clogged or damaged filter, your air purifier will not work properly, and you could damage your device. Many companies offer filter subscriptions, which can be a handy reminder.
According to the EPA, an air purifier can help reduce airborne contaminants, including viruses. However, it cautions that an air purifier is not enough to protect against COVID-19.
Some manufacturers, like BlueAir and Molekule, have tested their products against COVID-19 with positive results. A 2022 study found that PECO air purifiers like Molekule may help reduce SARS-CoV-2 molecules. Still, air purifiers should be part of a larger plan to prevent exposure to the coronavirus.
Air purifiers can help reduce viruses, but it’s important to choose the right one. For effective virus filtration, the EPA recommends air purifiers that can remove small particles ranging from 0.1 to 1 micron.
In addition to paying attention to particle size, you’ll want to make sure you’re choosing the right size unit for your space and double-checking that it has a high clean air delivery rate, or CADR, for smoke. The unit should also include a true HEPA filter.
There’s no official recommendation to use air purifiers if you have allergies. But air purifiers can help remove airborne particles like dust, dander, pollen, and mold.
Some studies have linked allergy symptom relief with the use of air purifiers. In fact, a 2018 study found that a HEPA air purifier in a bedroom helped with allergic rhinitis symptoms. Another 2018 study found that air purifiers with PECO filters reduced the participants’ allergy symptoms.
Yes. Air purifiers with a HEPA filter tend to be the best for filtering dust from your space. According to the EPA, HEPA filters can remove 99.97% of dust particles that measure 3 microns in diameter.
An air purifier with a HEPA filter is a good option if you want to minimize allergens like dust and dander. Newer technology like PECO is also designed not just to trap allergens but to destroy them.
An air purifier should be in a spot where it has space for airflow around the top, front, and sides. Tucking an air purifier behind furniture or beneath a shelf reduces its efficacy. Placing an air purifier on an elevated surface can be a good way to boost efficiency.
Keep in mind that air purifiers have a recommended capacity, so make sure you’re using a version that’s right for the space.
The time it takes an air purifier to clean a room largely depends on the size of the room, the air quality, and the speed or capability of your air purifier. Typically, a small room can be cleaned in about 30 minutes. Larger rooms may take several hours.
For the most effective air purifying, make sure you’re choosing a model that can handle the size of your room. For example, you don’t want an air purifier that’s best for a 250 sq ft office if you’re trying to clean a 1,500 sq ft living space.
If you’re experiencing chronic allergy symptoms, like coughing or sneezing, you likely have some allergens and contaminants hanging around. Regular snoring and frequent illnesses may also suggest that you have irritants in your air.
An air purifier might help if you notice lingering smells, heavy humidity, or visible pet fur tumbleweeds in your home.
If you use chemical-based cleaning products or paint regularly, an air purifier can reduce the smell.
Air purifiers make a lot of hefty claims in terms of what they can do for allergies and asthma. Finding an air purifier that uses a HEPA filter and a prefilter is probably your best starting point for finding something that works well.
Consider other concerns, such as noise level, energy use, and how often the filters need to be replaced when you’re looking for dust control in your space.
Last medically reviewed on August 22, 2023
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