When I think of fall, I think of colorful leaves crunching underfoot, slouchy sweaters, cute boots — and coming down with a cold. Growing up with three siblings and an English teacher father, the “back-to-school cold” was a well-known phenomenon in our family, and once one of us started sniffling, we knew it wouldn’t be long before we were all nursing sore throats and emptying tissue boxes. Looking back, I can’t help but think that if only we’d had access to the best air purifier for viruses and kept one in every room of our home, maybe we’d have been spared this unpleasant yearly ritual!
What is the best air purifier for viruses to buy in 2021?
- Best air purifier for Covid-19 : Molekule Air Pro
- Best smart air purifier for viruses : Blueair HealthProtect 7470i Smart Air Purifier
- Best mini air purifier for viruses : Molekule Air Mini +
- Best-selling air purifier for viruses on Amazon : Levoit Air Purifier
- Best air purifier for viruses and allergies : Honeywell PowerPlus True HEPA Air Purifier
- Best space-saving air purifier for viruses : Aura Air
- Best cooling air purifier for viruses : Dyson Pure Cool TP04 Purifying Fan
- Best air purifier for viruses and large spaces : Shark HE601 Air Purifier
- Best air purifier for viruses and small spaces : Filtrete Air Purifier
- Best quiet air purifier for viruses : My Happi
Of course, the reality of Covid-19 and the looming threat of variants make the idea of catching a virus much more serious than it was when I was a kid. Back then, getting sick was merely annoying. Now, it could be life-threatening. With people heading back to the office this fall, children back in the classroom already, and the Delta variant ravaging much of the world, many of us are wondering, “Are there any air purifiers that actually work to protect against Covid?”
If you’re considering investing in the best air purifier for viruses, we’ve got answers to some of the most frequently asked questions about air purifiers. Are air purifiers really worth it, or are air purifiers a waste of money? What is the best inexpensive air purifier? Do air purifiers use a lot of electricity? Should I leave an air purifier on all day? How do I choose an air purifier? Keep reading to find out — then shop our picks for the best air purifier for viruses, as well as the best air purifier for your particular space and needs.
Do air purifiers really work?
This is the big question! Thankfully, the answer is a resounding yes. Air purifiers do work. If they didn’t, then there surely wouldn’t be more than $1 billion in air purifier sales each year (and that’s in the United States alone!). However, there are different types of air purifiers, and some of them are more effective against viruses than others. The main difference between air purifiers is which filtration method they use.
Here’s a brief rundown of some of the types of filtration you’ll find as you shop for the best air purifier for viruses, and how they work to clean the air:
- High-efficiency particulate air (HEPA) filters can remove at least 99.7 percent of dust, mold, pollen, bacteria, and other particles — including viruses — from the air. These pleated air filters are made of interlaced glass fibers that create a maze to trap particles, and are commonly used in vacuum cleaners as well as air purifiers. Some of the best air purifiers for viruses use a HEPA filter, whether it’s alone or in combination with another type of filtration technology. (We like the Shark HE601 Air Purifier, available from Amazon for $349.99).
- Ionic filters work very differently than HEPA filters. Rather than catching particles in a maze of fibers, they charge the airborne particles with ozone as they pass through the air purifier, creating an electrostatic attraction that catches the particles on a set of metal plates. The particles remain inside the unit, so you don’t breathe them in. Some people, however, worry that the ozone byproduct of ionic filtration could be harmful. The AirTamer A302, available from Amazon for $79.99, features electrostatic purification technology and garners good reviews.
- Activated carbon filters trap volatile organic compounds (VOCs) that are commonly released from household products like new furniture, aerosol sprays, and mattresses. They filter gases through a bed of activated carbon (also called activated charcoal) and are very good at getting rid of odors such as cigarette smoke. They cannot, however, remove mold, dust, pollen, or other fine particles from the air. The Dyson Pure Cool TP04 purifying fan, available from Dyson for $449.99, uses activated carbon filtration in combination with a HEPA filter.
- Photocatalytic Oxidation (PCO) filtration combines ultraviolet light rays with titanium dioxide, resulting in a photocatalytic process that breaks pollutants down into carbon dioxide and water, rendering them harmless. This effectively cleans the air and eliminates allergy triggers like mold, fungi, dust mites, and pet dander. It works on particles of all sizes — but its effectiveness against viruses, while promising, has not been scientifically proven. Pure Enrichment’s PureZone Elite air purifier, available from Amazon for $149.97, is a popular PCO air purifier that earns raves from buyers.
- Photo Electrochemical Oxidation (PECO) grew out of PCO filtration and takes it a step further. PECO filters are able to destroy pollutants at a microscopic scale, including VOCs and viruses one thousand times smaller than HEPA filters can handle. PECO technology uses free radicals—the same radicals used to destroy cancer cells—to break down pollutants including viruses, bacteria, mold, allergens, and chemicals.There is no ozone byproduct to worry about, and in fact, PECO filtration may actually lessen the amount of ozone in your air. Molekule air purifiers (Buy from Amazon, starting at $399) use PECO filtration, and are some of the most popular air purifiers on the market today.
Still not sure which type of air purifier is the best air purifier for viruses? Don’t worry — you don’t need to be a scientist to choose an air purifier that will help you breathe clean air and stay healthy! Scroll down to shop our picks, where we break the features of each air purifier down in easy-to-understand language.
What is the best air purifier on the market today?
That all depends on what you need in an air purifier, and where you’ll use yours. The best air purifier for viruses may be different from the best air purifier for mold, or the best air purifier for allergies.
Some of the most popular air purifier brands include Blueair air purifiers, Dyson air purifiers, Levoit air purifiers, Coway air purifiers, Molekule air purifiers, Winix air purifiers, and Honeywell air purifiers. Which one is right for you will depend on several factors, including your budget, the size of your space, and what you are looking for in an air purifier.
What is the best air purifier for your house?
The best air purifier for your home will depend on where you want to put it, how big an area you want to cover, and what you primarily want it for. Since we’re focusing on the best air purifier for viruses in this article, you’ll want to get one that uses filtration proven to be effective against airborne viruses, like the Filtrete Air Purifier (Buy from Amazon for $150.30).
Think about your space, and where you will keep the air purifier. A larger air purifier that sits on the floor will take up more room, but can work well if you have the square footage to spare. Many of the best air purifiers for viruses are designed to coordinate with your décor and even look stylish in your space! Our roundup below has a wide variety of air purifiers, from compact to larger models — including one that hangs on the wall, and one that you wear around your neck!
Do air purifiers use a lot of electricity?
Any device that plugs into an outlet is going to increase your utility bill to some extent, but running an air purifier (or even several) doesn’t have to break the bank. Most air purifiers cost less than one dollar per day to run, even if you leave it powered on 24/7. Look for an Energy Star-rated air purifier to make sure it’s made to run as efficiently as possible, use only the size you need to cover your square footage, change the filter regularly, and you’ll find that running the best air purifier for viruses doesn’t add significantly to your electric bill.
Are air purifiers really worth it?
If you’re wondering whether it’s really worth the money, time, and effort you’ll spend finding the best air purifier for viruses, I get it. Since the start of the pandemic, we’ve been asked to change so much about how we live. We’ve bought the best face masks to prevent Covid-19 transmission, we’ve stopped touching our faces, and we’ve washed our hands so much they got chapped (at least, mine did!). But with the new, more contagious delta variant spreading widely, and many of us resuming normal indoor activities, this isn’t the time to fool around. Investing in a good air purifier for the space you’ll be spending the most time in is a good way to lower your risk of contracting Covid — not to mention other viruses, like the common cold or the flu.
Keep scrolling to shop our picks for the best air purifier for viruses, and stay safe and healthy this winter!
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15 Best Air Purifiers for Viruses in 2021
Why we like it:
- Patented PECO technology destroys airborne viruses, bacteria, mold, allergens, and chemicals
- Designed for larger spaces, up to 1,000 square feet
- Woman-founded, owned, and operated company
If you’re serious about leveraging the benefits of air filtration to help protect against Covid-19, check out the Molekule Air Pro. It’s a professional-grade air purifier that’s designed to work in commercial spaces up to 1,000 square feet — but that doesn’t mean you can’t use it at home.
What sets this unit apart is that, rather than using HEPA filtration (the standard for most consumer air purifiers), which simply captures viruses, mold, and other airborne troublemakers, it uses patented PECO nanotechnology (that’s Photo Electrochemical Oxidation) to actually destroy those pollutants.
With its anodized aluminum housing and vegan leather handle, this air purifier adds a stylish touch to any room, in addition to putting your mind at ease about the air you breathe. We also love that Molekule was co-founded by a woman, Jaya Rao, and is woman-owned and operated. The company is donating air purifiers to schools, businesses, and people in need during the twin crises of the Covid-19 pandemic and the wildfires raging across California and the Pacific Northwest. (The Woman’s World review unit was donated to a high school in New York City, along with a six-month supply of air filters).
Happy customer: “This machine is a BEAST and I mean that in the best possible way. The air smells different in our house — for the better! It’s so quiet my husband didn’t notice it was on. I feel much better knowing our house is free of all my allergens, viruses, and chemicals”.
Why we like it:
- Premium LED interface
- GermShield technology provides 24/7 protection against viruses and bacteria
- App- and voice-controlled
For some, smart devices may still seem a bit futuristic or even unnecessary, but they can really come in handy! Take this smart air purifier by Blueair, for example. Compatible with Google Assistant and Alexa, it services rooms up to 418 square feet, and features a clean air countdown to show you its progress. You can also use the Welcome Home setting to have it work its magic while you’re out, so you can return to a clean breathing environment, and the SmartFilter alerts you when it’s time to be replaced. Speaking of filters, this device uses HEPASilent Ultra technology to remove 99.97 percent of airborne particles, and a test done with the HealthProtect 7400 series actually showed a 99.99 percent reduction in airborne live SARS-CoV-2.
Happy customer: “I’ve really felt at ease since setting this device up because I know the air in my home is clean and safe. This is a powerful purifier that is easy to set up and connect. The app is easy to navigate and provides a ton of info on what’s going on in your home. All that information is available on the device itself, too, which I appreciate because I don’t always want to pick up my phone and open an app. It’s very quiet on the lower settings. You can’t even hear it until you hit two, where it starts making some noise, but it’s nowhere close to bothersome … I have owned several air purifiers over the years, but this one is definitely the smartest and most effective. The noticeable difference it makes in air quality and the peace of mind it brings make it well deserving of my highest recommendation.”
Why we like it:
- Smaller, more affordable version of the Molekule Air Pro
- Destroys viruses and other allergens, rather than just capturing them
- Ideal for smaller bedrooms and offices
If you love the idea of the Molekule Air Pro, but don’t have a large space (or a large budget), the Molekule Air Mini+ might be just the thing for you. Like the Air Pro, the Mini+ uses Photo Electrochemical Oxidation (PECO) nanotechnology to destroy viruses, allergens, bacteria, and mold — but it’s designed to be used in a smaller space, like a bedroom or home office up to 250 square feet. It’s got five speeds to choose from, is portable enough to carry with you from room to room (or bring with you on the road and use in your hotel room), and connects to WiFi so you can control it with your smartphone. Plus, it’s quiet and uses very little energy, so you can run it 24/7 without running your electric bill up! Note that there are two models of the Molekule Air Mini — the Mini+ and the regular Mini, which is only $399. The Mini+ has a few more fancy tech features, but both keep a small room’s air just as fresh. Compare and see which one you like best!
Happy customer: “With Covid going around, I was testing out various purifiers and this one is my favorite. It’s sleek and modern-looking, virtually silent, and auto detects the air quality, ensuring that it’s operating on the most effective mode. Another feature I love about the Molekule Mini+ is that it destroys, not just traps particles. I had a bit of a hard time lining up the canister correctly and getting it to start and sync with the app, but the company was great about helping me troubleshoot, ensuring I had everything figured out. I’m so impressed that I’m actually getting another one to donate to my child’s classroom for this year.”
Why we like it:
- Affordable, and has over 33,000 5-star ratings on Amazon
- 3 fan speeds
- Timer lets you turn it to “sleep mode,” which is nearly silent
How often do you need to dust? If you live in a city or an older house, the answer is likely, “constantly.” No matter how often and how thoroughly you clean, that layer of dust builds up again all too quickly. But there’s another way to tackle your dust woes, besides breaking out the can of Pledge and microfiber cloth on a regular basis. An air purifier can significantly reduce the amount of dust in the air — and therefore, the amount of dust that settles on your bookshelves, picture frames, and windowsills. This Levoit air purifier, besides being one of the most affordable in our roundup, is also a workhorse when it comes to cleaning the air and keeping your home free of dust and other allergens. With three fan speeds, a filter that’s easy to change, and a timer that allows you to set a “sleep mode” that’s whisper-quiet, this no-frills air purifier gets the job done for less.
Happy customer: “I live in an older house that was built in the 1960s, and dust is a big problem. It gets everywhere. I vacuum my bedroom several times a week, but there’s just no getting ahead of it. Every 24 hours, every tabletop is covered in a thin layer of dust, even though the windows and door are closed almost all day and night … This is the first air purifier that actually makes a marked difference in terms of dealing with the dust that plagues me so. Unlike [other air] purifiers, I can actually see the dust being sucked in through the device and into the filter, which is very satisfying. On top of being extremely effective, this air purifier is far more compact and attractive than any other I’ve owned.”
Why we like it:
- Cleans rooms up to 530 square feet
- HEPA filter
- Comes with 4 cleaning levels
Honeywell is one of the top brands recommended by allergists, and the PowerPlus True HEPA air purifier is a great option for those who suffer from dust, smoke, and pollen allergies. It captures up to 99.97 percent of microscopic allergens, and helps reduce up to 99.9 percent of certain airborne viruses, bacteria, and mold spores. The four intuitive cleaning modes automatically adjust their levels based on readings of the room’s air quality, making this device a true smart machine. Best of all, it’s effective in spaces up to 530 square feet large, so even the biggest rooms in your home will be easier to breathe in.
Happy customer: “This filter has been a godsend for my wife. She suffers from severe allergies, especially dust. We have kept this running 24/7 and she has seen a dramatic improvement in her nasal clarity. We also like that you can dim the control panel so that the lights don’t bother us at night. It is easy to use, and not so large as to be intrusive. You can also find reasonably priced replacement filters, which is also a huge plus.”
Why we like it:
- Captures and kills 99.9% of viruses and bacteria
- Saves space by attaching to the wall or ceiling
- Compatible with Alexa and Google Assistant
Short on floor space? No problem! This professional-grade air purifier from Aura can be mounted to the wall or ceiling to save precious room in your home. Featuring a patented Ray Filter, which targets airborne particles as small as 0.3 microns, in addition to a pre-filter to trap larger particles, the Aura Air is able to detect and kill up to 99.9 percent of bacteria and viruses. Because of this, it’s received positive reviews by medical professionals (testimonial included below), so you can feel confident about using it to purify your home. It is one of the pricier items on our list, but it spans large spaces up to 600 square feet and comes with a one-year warranty for peace of mind.
Happy customer: “I added the Aura Air filter to our isolation room. The isolation room is also used for patients with compromised immune systems who may be more susceptible to viruses such as SARS-CoV-2. Aura Air’s an all-in-one indoor air purification and quality intelligence system that purifies and vigilantly monitors in real-time — which is what we need for critical areas of care like this.” — Dr. Hoa Nguyen, American Medical Center
Why we like it:
- Combined activated carbon and HEPA filters capture 99.97 percent of airborne allergens and pollutants
- Adjusts to flow backward or forward, depending on whether you want a cooling fan effect or not
- Automatically detects air quality and exports data to the Dyson Link app so you can monitor
If you suffer from seasonal allergies or sensitivity to mold, pollen, and other indoor allergens, this Dyson air purifier will be your new best friend. This sleek machine, which is touted as “the only purifying tower fan to clean a whole room properly,” filters out 99.97 percent of microscopic allergens and pollutants that otherwise might have you sneezing, sniffling, and rubbing your itchy eyes. This best-selling air purifier can also be used as a fan to cool your space — an adjustable oscillation angle projects purified air around the whole room from 45 to 350 degrees — or you can direct the airflow backward when you don’t want to feel a breeze.
Happy customer: “I have allergies and have experienced sinus and chest congestion for years. I didn’t know how congested I was until I plugged my TP04 in and within a matter of a couple of hours experienced a relief in sinus pressure and sneezing due to the bad air quality in my home. I enjoy the ability to monitor the air quality from my iPhone after downloading the Dyson Link app.”
Why we like it:
- Covers up to 1,200 square feet
- 6-fan airflow
- User-friendly remote control
Looking to clarify air in an extra-large space? The Shark HE601 is our pick, thanks to its span of up to a whopping 1,200 square feet — more than the total area of many city apartments! It’s powered by six micro-fans to quietly and evenly distribute airflow, while Clean Sense IQ adjusts the speed depending on the level of air pollution. A user-friendly remote control conveniently enables you to operate it from a distance, and in addition to keeping harmful contaminants at bay, this machine is also ideal for eliminating unwanted odors from pets and kitchen mishaps. As if that wasn’t enough, an anti-allergen HEPA multi-filter captures up to 99.97 percent of dust, dander and allergens — sniffles, be gone!
Happy customer: “On the lowest fan setting, it’s so quiet that I forget that it’s running … The Shark’s auto mode kicks up or down depending on air quality, and its electronic display lets me know exactly what’s going on. The touch controls are both easy to use and intuitive. And the unit can clean the air in a large area. It even comes with a remote control that allows me to change the settings without getting up.”
Why we like it:
- HEPA filter captures 99.97% of airborne particles
- Filter change indicator light tells you when it’s time for a new filter
- Cleans rooms up to 250 square feet
This Filtrete Air Purifier features true HEPA filtration with protection from allergens, bacteria, and viruses. It captures everything from dust, lint, dust mite debris, and pet dander, to mold spores, pollen, smoke, smog, exhaust particles, and ultrafine particles. The filter traps 99.97 percent of the airborne particles that are released from everyday activities such as frying food, dusting shelves, and even blow-drying your hair, and an electronic filter change indicator on the control panel lets you know when you need to put in a replacement. Its user-friendly design includes soft-touch buttons that let you easily change the fan speed, set a timer, dim the panel lights, and reset the filter change indicator.
Happy customer: “Just a lifesaver! I have a small art studio room and I use this air filter daily. We had to have unexpected work done inside our home and I am very sensitive and have allergies. So this made my small room a refuge. It is fairly noisy on level three, but it does seem to put out fresh cooler air and is very worthwhile to me. I put it on level three for about an hour before I go into work in my room, and then put down to level one. So it works for me! Very pleased with this product.”
Why we like it:
- 99.95% effective at capturing viruses and bacteria
- Whisper-quiet night mode
- Available in black or white
While we’d all like an air purifier that’s powerful enough to clarify our surroundings, we don’t necessarily want to hear it working! Enter: the My Happi air purifier, which clocks in at just 28 decibels (or, as soft as a whisper) when on night mode. And, speaking of nighttime, the My Happi is ideal for purifying air while you sleep, as its small, lightweight build makes it the perfect size for your nightstand or dresser. While it’s not meant for large spaces (it’s designed to span a 150-square-foot radius), it’ll trap up to 99.95 percent of viruses and bacteria in the air, and features a UV-C lamp to eliminate secondary pollutants, making it a great option for smaller areas. And, since it weight less than five pounds, you can easily bring it from room to room, depending on where you are at different times of day.
Happy customer: “I love my Happi! Not only does it look adorable in my living room, I love how quiet it is — I can’t even hear it, but I can tell with the smart screen that it’s doing its thing. It’s so cool how I can monitor the quality of the air in real time, and whenever the color has turned to red indicating poor air quality, I can see the Happi working in real time to get it back down ASAP. Living in NYC, it’s so refreshing to know I’m breathing quality air in my own home.”
Why we like it:
- Sleek, compact design
- Energy-saving eco mode
- 4-stage filtration
Not all of us have extra space for large home appliances, which is why we love this compact design by Coway (and it’s super stylish, too!). But aesthetics aside, it’s also effective at eliminating contaminants and odors in spaces up to 361 square feet, thanks to a four-stage filtration system that belies its small size. While you can opt for one of three different fan speeds to suit your preferences, you can also rely on the air quality indicator to automatically sense indoor pollution levels and adjust accordingly. Best of all, the energy-saving eco mode will shut things down when air quality is at an optimal level, and start right back up once contaminants are detected.
Happy customer: “Amazingly efficient. After just one day [of] putting it in my living space during the day and in my bedroom overnight, my allergy symptoms are noticeably reduced. I have cat allergies all year, and seasonal allergies right now. I know it works, because when my cat took a slow saunter past it, the auto function went to ‘high’ because of all the dander around him. I’m using so many fewer tissues, this may pay for itself!”
Why we like it:
- Compatible with HomeKit, Alexa, and Google Assistant
- Three-stage filtration system
- Includes a handle for portability
At just over eight pounds, this small-yet-mighty air purifier is our pick when it comes to portability — it even includes a handle for easier transportation! But don’t be fooled by its compact size. It’s equipped with three-layer filtration — including a preliminary filter for things like dust and pet hair, an H13 True HEPA filter for protection from pollen and dander, and a third layer inner filter to combat smoke and odors — so you can rest assured you’ll be breathing cleaner, safer air, thanks to this device. Best of all, it’s incredibly simple to use, and is compatible with HomeKit, Alexa, and Google Assistant, in addition to Smartmi’s Link app, so you can control it even when you’re not nearby.
Happy customer: “The Smartmi is ready to go as soon as you unbox it. Just plug in the power supply and turn it on. It was very simple to use and the app for iOS was very easy to link to the air purifier. It is extremely quiet on auto mode, and it’s still very quiet, even at its highest mode. The look of it is very premium, and the leather strap actually comes in handy. Sometimes I use this in my living room and sometimes I move it to the bedroom … So far, I wholeheartedly recommend this air cleaner.”
Why we like it:
- Three-stage filtration
- Easy-to-clean filter
- Comes in three cute colors
Who knew an air purifier could actually make your room look better, and not just smell better? The simple, clean, and compact design of the Coway Airmega 150 air purifier, plus the fact that it comes in three color choices, makes it a favorite pick for anyone looking for an air purifier that will blend in with their home design. It also features three-stage filtration: a pre-filter, a deodorization filter, and a Coway Green True HEPA filter. A filter change indicator light lets you know when it’s time to clean the filter, which is super easy to pull out, and automatic speed control senses particles in the air and turns up or down accordingly. The intuitive air quality indicator light can be turned on or off, and this cute little machine keeps the air clean in spaces up to 214 square feet.
Happy customer: “It does everything as advertised. Easy to set up, took 10 minutes each. I use it in the bedroom at night and one in home office/den during the day … I’m super satisfied and couldn’t be happier. Looks great, easy to move around, easy to wipe clean, and quiet when you need it to be. I’d highly recommend this for small to mid-sized rooms, especially for a city apartment dweller like me who is stuck inside either due to heat, cold, or allergies. And now with Covid, a little extra sanitation on the air can’t hurt. Go for it!”
Why we like it:
- 3-stage air cleaning system and HEPA filter
- Visual display shows you the air quality
- Choose auto or sleep mode to save energy
This Winix air purifier is an updated version of their popular 5300 model. With its three-stage air cleaning system, it captures dust, pollen, pet dander, smoke, mold spores, VOC (volatile organic compounds), and everyday household odors, so you breathe fresh, clean air whenever it’s running. Since the Winix 5300-2 is rated for use in rooms up to 360 square feet (and is a pro at making spaces smell better), we think it’s perfect for the kitchen — but it would work equally well in a large bedroom or living space. It’s got a HEPA filter, an air quality visual indicator, a light sensor, and you can run it on auto mode or sleep mode.
Happy customer: “I have had this air cleaner for over a year, and to be honest it is the best purchase I have made in the area of improving the air I breathe. It is super quiet (even at full power) and removes any pending floating odors from the area wherever it is located … I am glad I went with my instincts to go ahead and buy it, I would most definitely recommend this to anyone looking to improve the air they breathe.”
Why we like it:
- Works within a 3-foot radius in all directions
- Weighs less than 2 ounces
- Compact and portable
Being out and about can be a little anxiety-inducing these days, especially for anyone with underlying health issues. As an extra precaution, an air purifier necklace is great for on-the-go use: We like the AirTamer A302, which weighs less than two ounces and can conveniently be worn around your neck or clipped to your clothing for effortless portability. Since it works in silence, feel free to wear it wherever you need to go without worrying about disrupting others around you, and take comfort in the fact that it helps clean air within a three-foot radius in all directions. In addition to its compact design, we also love that it’s filter-free (no replacements needed!), and instead relies on electrostatic purification technology to send healthy negative ions into your surroundings. When you’re not using it, simply store it in the included metal travel case for safekeeping.
Happy customer: “I have purchased three of these. I discovered it when looking for resources to help protect my immune system when going through chemotherapy. Also bought one for my dad to use when he went to doctors’ offices or was out and about to protect his immune system. We did not ‘catch’ the flu or a cold during the past year. I like that I felt safe when going to hospitals and doctors’ offices that are rife with people sick with infections. The purifier was easy to use and the battery life was more than acceptable; I only changed the batteries twice in the year … I have recommended this item to other cancer patients and nurses.”