We independently evaluate all of our recommendations. If you click on links we provide, we may receive compensation. What to Buy Healthy Home & Appliances The Best Air Purifiers for Allergies to Pollen, Pets & Smoke—After 3,000 Hours of Filtration We tested over 70 air purifiers from brands like Dyson, Honeywell, Levoit, and Blueair to find the best options for an allergy-free home. By Samson McDougall Samson McDougall Samson McDougall is a journalist, copywriter, editor and science graduate. Samson specializes in making the complex simple, using the English language to democratize knowledge through highly effective, accessible communication. health's editorial guidelines and Lauren Paige Richeson Lauren Paige Richeson Lauren Paige Richeson is a writer and editor at Health. She's the author of Avocado Obsession Cookbook and covers a wide range of lifestyle and wellness topics for some of the world's most popular publications. health's editorial guidelines Updated on November 27, 2024 Medically reviewed by Michael Menna, DO Medically reviewed by Michael Menna, DO Michael Menna, DO, is currently an attending emergency medicine physician at White Plains Hospital in White Plains, New York, with nearly 10 years of experience. learn more In This Article View All In This Article Our Top Picks Reviews Our Testing Process Our Experts What to Know We Also Tested Who We Are Health For anyone with allergies or asthma, maintaining good air quality is essential. Surprisingly, indoor air can often be more polluted than outdoor air due to poor ventilation and the buildup of dust, pet dander, and chemicals. A portable air purifier can help by filtering out contaminants like pollen, mold spores, and smoke to release cleaner air back into the room. This makes breathing easier for allergy-sensitive people and reduces the likelihood of asthma attacks, lung conditions, and respiratory issues. According to air-quality specialist Dr. Paula Olsiewski, the best air purifiers for allergies are equipped with True HEPA filters that trap 99.97% of airborne particles as small as 0.3 microns and can purify a room in 15 minutes. Also, look for activated carbon filters to remove odors and chemicals, a high clean air delivery rate for quick cleansing, quiet operation, and low maintenance costs. To find the best models for different allergy concerns, we've tested over 70 air purifiers from top-rated brands like Blueair, Dyson, Shark, and more. Each air purifier was evaluated in the Health Lab and our homes and rated on how well they reduced allergens after weeks and months of use. In addition, an allergist from our Medical Expert Board reviewed this article for medical and scientific accuracy. What to Look for in Air Purifiers for Allergies Understanding these key features and terms related to air purifiers can assist you in selecting the best option for your allergy needs.True High-Efficiency Particulate Air Filters (HEPA) - The gold standard for allergy relief. These filters can capture 99.97% of particles as small as 0.3 microns and eliminate common allergens like dust, pollen, mold, and pet dander. Every air purifier we tested is HEPA compliant.Multi-Stage Filtration Systems (MFS) - Many air purifiers for allergies use a combination of filters, such as pre-filters, HEPA filters, and activated carbon filters, to capture more pollutants and protect against both particulate and gaseous allergens.Particulate Matter 2.5 (PM2.5) - Filters that capture PM2.5 or smaller are key for allergen control. PM2.5s are fine particles, like vehicle emissions, smoke, and bacteria, that are small enough to enter the respiratory system and can cause or worsen allergy symptoms.Clean Air Delivery Rate (CADR) - Measures how quickly a purifier can remove smoke, pollen, and dust from the air of a specific room size. A higher CADR rating means more efficient air cleaning. When choosing an air purifier, look for high CADR ratings for your allergen concerns and a CADR that matches your room size for the best performance.Total Volatile Organic Compounds (TVOC) - Chemicals emitted from household items like paint, furniture, cleaning products, and even dry-cleaned clothes can worsen allergies, asthma, or chemical sensitivities. Air purifiers with carbon filters or special VOC filters can help reduce TVOCs in the air. Our Top Picks Best Overall: SALE Levoit Core 400S Smart Air Purifier at Amazon $220 $178 Jump to Review Best for Odors: SALE Blueair Blue Pure 411i Max Air Purifier at Amazon $170 $119 Jump to Review Best for Asthma: SALE Dyson Purifier Humidify+Cool Formaldehyde at Amazon $1,000 $800 Jump to Review Best for Viruses and Bacteria : Clorox Large Room Air Purifier at Amazon $150 Jump to Review Best for Dust: SALE Winix 4-Stage True HEPA Air Purifier at Amazon $250 $156 Jump to Review Best for Pollen: Rabbit Air A3 Air Purifier at Amazon $750 Jump to Review Best for Mold: EnviroKlenz Mobile Air System at Amazon $580 Jump to Review Best for Pet Allergies : GermGuardian Air Purifier at Amazon $110 Jump to Review Best for Smoke: SALE Dyson Purifier Cool Purifying Fan at Amazon $650 $349 Jump to Review Best for Quiet Operation: Kenmore 1500e Air Purifier at Amazon $170 Jump to Review Best Overall Levoit Core 400S Smart Air Purifier PHOTO: Health / Henry Wortock $220 $178 at Amazon $290 at Walmart View on Levoit.com Why We Like It The Levoit Core 400S is an excellent choice for anyone looking to invest in their first air purifier or upgrade to a more powerful model. Designed to tackle common allergens like dust, pollen, and pet dander, this purifier combines advanced filtration with convenient smart features, making it a top choice for allergy relief. Its 3-stage filtration system includes a pre-filter for larger particles, an H13 True HEPA filter that captures 99.97% of airborne allergens like pollen, dust, and pet dander, and an activated carbon filter to neutralize odors and VOCs. It can purify rooms up to 403 square feet, perfect for medium to large spaces. This purifier features AirSight™ Plus Technology—a smart laser dust sensor that detects airborne particles, provides real-time air quality updates, and automatically adjusts fan speed based on particle levels. The easy-to-use VeSync app allows you to monitor air quality, schedule operation times, and receive filter replacement notifications from your smartphone. The Levoit 400S is also compatible with Amazon Alexa and Google Assistant, offering convenient voice control for effortless daily allergy management. It's Worth Noting The filter lifespan of up to six months and a pre-filter that only needs cleaning every 2 to 4 weeks. Product Details Dimensions: 10.79 x 10.79 x 20.47Room Size: 403 square feetCADR: 260 CFMNoise Level: 24 to 52 dB Best for Odors Blueair Blue Pure 411i Max Air Purifier PHOTO: Health $170 $119 at Amazon $136 at Target View on Blueair.com Why We Like It Super effective at improving air quality, the Blueair Blue Pure Max 411i was a clear choice for our best odor control pick because it significantly reduced odor and allergens in the air. During our 30-minute test, we recorded excellent PM2.5 and TVOC reductions—well above other models we tested. Our allergies and sense of smell improved after just 30 minutes. Its wireless connectivity is a nice touch—allowing remote adjustments and filter usage updates. We also appreciated the light-dimming and night mode settings, which made it easy to sleep with the purifier in the bedroom. it's a great pick for reducing odors and small particle removal. It’s Worth Noting Switching the light-dimming mode from bright to dark night mode was somewhat challenging, and it may take time to get used to. Product Details Dimensions: 18.9 x 10.6 x 10.6Room size: 219 square feetCADR: Smoke 141, Dust 125, Pollen 114Noise Level: 18 to 46 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Asthma Dyson Purifier Humidify+Cool Formaldehyde PHOTO: Health $1,000 $800 at Amazon $930 at Walmart $1,000 $800 at Best Buy Why We Like It Dry air can be uncomfortable for people with asthma, leading to more coughing, wheezing, and trouble breathing. Adding some moisture to the air can help soothe irritated airways. The Dyson Humidify+Cool Purifier combines air purification with humidifier controls to minimize common asthma triggers like formaldehyde, dust, and dry air. The Dyson purifier humidifier automatically detects and captures pollutants while delivering a hygienically humidified mist. An indoor humidity level between 30% and 50% is ideal for maintaining moisture without encouraging mold growth or dust mites, which can worsen asthma symptoms. This model comes with Dyson’s advanced filtration technology, including a True HEPA filter, an activated carbon filter that neutralizes VOCs, and a catalytic filter that destroys formaldehyde gas and odors. In our testing, this all-in-one unit effectively removed 99% of airborne pollutants within 10 minutes. The setup was easy, and the intuitive control panel displayed the purifier's power level and the humidifier's operating percentage. We appreciated the smart features, such as voice control and monitoring through the Dyson app. While the Dyson Purifier Humidify+Cool Formaldehyde is the most expensive option on our list, its ability to purify air and add moisture makes it ideal for those with asthma needing humidity control. It's Worth Noting We noted some difficulty during set-up and filter replacement but found the included set-up video helpful. Product Details Dimensions: 36.33 x 12.28 x 11.02 Room Size: 400 square feetCADR: Not disclosedNoise Level: 49 dB PHOTO: Health PHOTO: Health Best for Viruses and Bacteria Clorox Large Room Air Purifier PHOTO: Health $150 $135 at Amazon $142 at Target $150 $135 at Walmart Why We Like It The Clorox Large Room Air Purifier impressed us with its ability to quickly improve air quality, ease of use, and large room coverage. It is specially designed to combat germs with a True HEPA filter that captures 99.97% of particles as small as 0.1 microns, along with two additional filters for larger particles and odors. This purifier's advanced filtration technology makes it a top choice for creating a safer indoor space. During our testing, the Clorox purifier significantly reduced room odors in just 30 minutes. The air felt noticeably fresher, leaving the room with an overall cleaner feel and a clear difference in air quality. Whether on low or high settings, the cylindrical three-stage filter did a great job of filtering air from every corner. The model also includes an air quality indicator that displays the air’s cleanliness—a useful feature for those who like real-time feedback. The air purifier has four fan speeds and even the highest speed, while louder, didn't disrupt conversations or TV time. The control panel was easy to use, with subtle lighting and clear buttons for power, fan speed, and Auto mode. It’s Worth Noting The noise level on the highest setting is slightly louder than other devices we tried. Product Details Dimensions: 10 x 10 x 19 Room size: 320 to 1500 square feetCADR: Smoke 206, Dust 219, Pollen 232Noise level: 44 to 59 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Dust Winix 4-Stage True HEPA Air Purifier PHOTO: Health $250 $156 at Amazon $160 at Target $269 at Walmart Why We Like It Indoor dust can be a major trigger for allergies and respiratory issues, especially for people sensitive to allergens like dust mites, which thrive in warm, humid environments. The Winix 5500-2 Air Cleaner with PlasmaWave Technology is a top choice for dust and overall allergen control in the home. With a four-stage filtration system, it excels at trapping dust and other airborne particles. The system includes a pre-filter for larger particles, an activated carbon filter to reduce odors, a True HEPA filter that captures 99.97% of particles as small as 0.3 microns, and PlasmaWave technology to neutralize pollutants without producing ozone. Designed to handle spaces up to 1,740 square feet in one hour, the Winix 5500-2 effectively purifies the air, making it ideal for large rooms. In our testing, it quickly adjusted to changes in air quality: when exposed to an air freshener, the air quality sensor immediately activated, turning orange and increasing the fan speed. After 30 minutes, we noticed a fresher, cleaner air quality throughout the room. This purifier operates quietly even on high, offers a convenient “sleep” mode, and comes with a user-friendly control panel and remote control. It's Worth Noting The LED indicator is quite bright, so we recommend using this air purifier in your living room, where the light won't trouble your sleep. Product Details Dimensions: 15 x 8.2 x 23.6Room Size: 360 square feetCADR: Up to 246Noise Level: 27 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Pollen Rabbit Air A3 Air Purifier PHOTO: Health $750 at Amazon View on Rabbitair.com Why We Like It This Rabbit Air A3 Ultra Quiet Air Purifier certainly packs a lot of features into its low-profile wall-mountable design. The robust, customizable six-layer filter—including a filter for large particles, activated charcoal, and BioGS HEPA filters—is impressive.' The pollen-specific filter adds an extra layer of targeted allergen control, making it perfect for seasonal allergy sufferers. During testing, we found that while this air purifier proved so-so regarding odor and particulate haze reduction, it removed small particles extremely well. We saw reductions in PM2.5 and TVOC of around 88% and 81% on the low setting. And in the highest (and still very quiet) setting, we saw reductions of 72% and 83%. From the clean LCD interface to auto light sensors to set fan speeds, wireless connection, air-quality sensors, a negative ion generator, and a super quiet five-speed fan, If the latest tech, connectivity, and good looks are your thing, this device could be worth the investment. It’s Worth Noting All the features in the world only provided a slight performance improvement over less expensive models we tested. Product Details Dimensions: 19.7 x 18.9 x 8.4Room size: 1070 square feetCADR: Pollen 315, Dust 262, Smoke 257Noise level: 44–62 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Mold EnviroKlenz Mobile Air System PHOTO: Health $580 at Amazon View on Enviroklenz.com Why We Like It With its advanced purification features, filtration performance, and durability, the EnviroKlenz Mobile Air System is the best air purifier for mold exposure. It features a hospital-grade HEPA filter, a proprietary mineral filter that neutralizes VOCs and microscopic pathogens, and UV-C light technology to inhibit mold growth and other microorganisms. The EnviroKlenz Air Systems are tested and proven to effectively remove common mold and fungi at a 99.9% removal rate, including common species Aspergillus niger and Penicillium citrunim. After using it in a 300-square-foot bedroom, we saw a noticeable reduction in congestion and allergy symptoms overnight. The system is easy to operate, with a single dial offering four fan settings: whisp-air, low, medium, and high. The whisp-air setting is quiet, and even the highest fan setting is mild enough for comfortable sleep. It's designed with wheels and can cover up to 1,000 square feet with 3-5 air exchanges per hour. We also appreciate that it includes 2 years' worth of filter replacements. Despite the high price tag and lack of features like digital displays or app controls, the EnviroKlenz Mobile Air System is a reliable investment for long-term improvement in indoor air quality and control of mold. It's Worth Noting While there is a slight mineral scent when first used, it dissipates within an hour. Product Details Dimensions: 15 x 15 x 19Room Size: 290 square feetCADR: Up to 96 CFMNoise Level: 32 to 64 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Pet Allergies GermGuardian Air Purifier PHOTO: Health $110 at Amazon View on Lasko.com Why We Like It We’ve found the GermGuardian Airsafe+ to be an excellent air purifier addition for pet-friendly homes. It’s affordable, easy to use, and perfect for pet owners looking to reduce indoor allergens. This purifier’s True HEPA filter effectively captures 99.97% of airborne particles, including pet dander, dust, pollen, and other allergens as small as 0.1 microns, and an activated carbon pre-filter traps pet hair and other large particles. We set it up in our medium-sized living room, where our pets spend the most time, and it made a noticeable difference. After consistently using it, we noticed less hair to sweep up during daily cleaning and fewer allergy symptoms like sneezing, itching, and occasional coughing. While it didn’t fully eliminate cooking odors, it undoubtedly reduced the amount of pet hair and dander in the air. The setup was straightforward: a simple four-setting interface with an Auto mode and air quality indicator. We especially liked the Night Mode, which lowers fan noise by about 10%—perfect for quiet evenings. It’s compact enough to fit well in a medium-sized room but sturdy enough to handle high-traffic pet areas. It's Worth Noting The fan noise can be disruptive for users sensitive to sound, particularly when the unit is running on medium or high settings. Product Details Dimensions: 12 x 9.75 x 9.75Room size: 1040 square feetCADR: Smoke 139, Dust 146, Pollen 150Noise Level: 24 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Smoke Dyson Purifier Cool Purifying Fan PHOTO: Health $650 $349 at Amazon $350 at Target $650 $350 at Walmart Why We Like It For those sensitive to smoke and other fine particles, the Dyson Purifier Cool Smart Air Purifier and Fan (TP07) stands out with its ability to remove pollutants rapidly and thoroughly. Designed with advanced filtration and dual functionality, this high-end unit quickly cleared smoke and pet hair from the air in our tests, noticeably improving air quality in just 5 to 10 minutes. This Dyson features a 360-degree HEPA filter with activated carbon that captures 99% of airborne pollutants. It oscillates up to 350 degrees, distributing cool, purified air throughout the room—perfect for large spaces where smoke or other allergens tend to linger. Setting it up took less than five minutes, and its quiet operation, even on the highest fan speed, makes it suitable for any room in the house. The night mode dims the display and lowers the fan speed, making it ideal for nighttime use. It's easy to manage and monitor, with options to control via the remote or Dyson’s user-friendly mobile app, which tracks air quality, humidity, and temperature. The unit even includes a filter replacement indicator, alerting you when a new filter is needed, generally once a year, keeping your air purifier efficient and hassle-free. It's Worth Noting The unit is on the taller side, measuring 41 inches from base to top. Product Details: Dimensions: 7.7 x 8 x 41Room Size: 99 square feetCADR: Up to 82.1 CFMNoise Level: 32 to 64 dB PHOTO: Health PHOTO: Health Best for Quiet Operation Kenmore 1500e Air Purifier PHOTO: Health $170 $150 at Amazon $170 at Walmart View on Kenmorefloorcare.com Why We Like It The Kenmore 1500e Air Purifier with SilentClean HEPA Technology is great for creating cleaner air without disrupting the peace. It provided significant air filtration, and the “SilentClean” technology produced the lowest noise level out of all our tests. The Kenmore 1500e contains a three-stage filtration system with a pre-filter for capturing larger particles like hair and lint, a True HEPA filter that removes dust, pollen, and pet dander, and an activated carbon filter to reduce odors from cooking, pets, and smoke. This model can purify up to 1,500 square feet, making it suitable for larger rooms. A user-friendly digital display offers control over modes, fan speeds, and timers, while a filter maintenance indicator keeps users informed when replacements are needed. With its powerful yet silent operation, It's Worth Noting Its large size and bulky design may not fit seamlessly into smaller rooms or areas with limited space, which can be inconvenient. Product Details Dimensions: 10.24 x 10.24 x 19.13Room size: 1500 square feetCADR: Not listedNoise level: 40 to 50 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Bedrooms Bionaire True HEPA 360 UV Air Purifier PHOTO: Health $149 $120 at Amazon $180 at Target Why We Like It The Bionaire True HEPA 360° Air Purifier is ideal for creating a cleaner, healthier sleep environment thanks to its quiet operation and 360-degree air intake that provides complete room coverage. Equipped with a True HEPA filter, this purifier demonstrated impressive abilities for small-particle filtration, exceeding our expectations. Even on the highest setting, the fan operates quietly, resembling ambient white noise. Its gentle three-speed fan and dim light make it perfect for nighttime, giving you clean air without interrupting sleep. Its compact design fits well in small spaces and includes a timer, a nightlight, night mode, an ionizer, and a filter replacement indicator. It’s Worth Noting Initially, the buttons are slightly difficult to see, which could cause issues if using it at night or in dimly lit rooms. Product Details Dimensions: 17.5 x 10.7 x 11.5Room size: 155 square feetCADR: 113Noise Level: 30 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Best for Small Spaces Levoit Core Mini Air Purifier PHOTO: Health $50 at Amazon $42 at Target $50 $40 at Walmart Why We Like It The Levoit Core Mini Air Purifier is compact and remarkably effective, making it a top choice for controlling allergens in smaller settings. It includes a three-stage filtration system with a pre-filter, HEPA filter, and activated carbon filter, which work together to eliminate mold spores, dust, and other airborne particles. Our testing showed outstanding performance on the high setting, thoroughly purifying the air despite its smaller size. Thanks to its 360-degree air intake, the purifier provides consistent and fresh airflow throughout the room. At under 3.5 pounds, this lightweight, portable purifier boasts a sleek, minimalist design that can easily fit in with any home decor. Its setup and operation are simple, with a single-button control for adjusting fan speed and a filter change indicator light, making it accessible for users of all ages. The Levoit Core Mini is one of the quietest models we tested, functioning almost silently, even on high. It also features a diffuser pad for essential oils, allowing you to infuse the purified air with a pleasant fragrance. Considering its affordable price, effectiveness, and quiet performance, the Levoit Core Mini provides excellent value for anyone looking to manage allergies and enhance air quality in smaller rooms. It's Worth Noting The power cord was relatively short, which might limit where you can place it in your home. Product Details: Dimensions: 6.5 x 6.5 x 10.4 Room Size: 178 square feetCADR: 46 CFMNoise Level: 24 to 36 dB PHOTO: Health PHOTO: Health Best for Kids Pure Enrichment Bear Air True HEPA Air Purifier PHOTO: Health $150 $100 at Amazon $100 at Target $100 at Kohls.com Why We Like It The Pure Enrichment PureBaby Bear Air Purifier offers good air purification with child-friendly features, perfect for protecting kids from allergens and airborne pollutants. Its cute bear design adds charm to any nursery or child’s room. Equipped with a true HEPA filter, it captures mold spores, dust, and allergens, while the UV lamp reduces bacteria for extra protection. The touch-button interface lets parents easily adjust fan speeds, set timers, activate the UV light, and engage the child lock. It features a night light with seven soothing colors and gentle illumination without disturbing sleep. Operating quietly across three fan speeds, it creates a calming background noise. With filters that need to be replaced only twice a year, this air purifier requires minimal maintenance, making it an excellent choice for creating a healthier environment for children. It's Worth Noting If UV lights break, mercury bulbs can release toxic substances, requiring careful handling, especially in nurseries. Product Details Dimensions: 11.1 x 8.7 x 14.6Room Size: Up to 263 square feetCADR: 70 CFMNoise Level: 28-50 dB PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health PHOTO: Health Our Testing Process We conducted a comprehensive six-month test of over 70 popular air purifier models, evaluating their allergen removal performance in both home settings and controlled environments at the Health Lab.In our real-world tests, we used each air purifier at least once a week for six months. We documented our insights every one, three, and six months, detailing its durability, maintenance ease, and air quality effectiveness. For our lab tests, we assessed air purifiers based on their setups, noise levels, and effectiveness at reducing PM2.5 and VOCs. In both tests, each air purifier was rated for the following factors: Setup: We timed how long it took to set up the air purifier, from unboxing to its first use. We evaluated the ease of assembly based on the clarity of the instructions and the straightforward nature of filter installation.Design: We evaluated the purifier’s build quality, size, and appearance to see how well it fits into a home environment. Practical design elements like cord length, display options, and feature convenience were assessed to determine user-friendliness and aesthetic appeal.Noise Level: We used a decibel meter to measure noise levels at each fan setting, from quietest to loudest, to determine if the purifier could operate without disrupting daily activities or sleep.Features: We tested additional features, including app and smart home compatibility, filter life indicators, and air quality sensors. Features were rated based on functionality, ease of use, and how well they contributed to the overall user experience.Effectiveness: In the lab test, we used three conference rooms to match manufacturers' CADR ratings for different room sizes. In controlled air quality chambers, we measured baseline levels of PM2.5 and VOCs. We then evaluated improvements in air quality after operating each air purifier on low and high settings for 30 minutes. By introducing contaminants like incense smoke, dust, and pet hair, we assessed their effectiveness, recording reductions in PM2.5 and total VOCs ranging from 60% to 90%.Filter Inspection: After each test, we visually inspected each purifier’s filter to determine how well it captured allergens like pet hair, dirt, and dust, providing insight into each model’s overall efficiency.Value: We assessed each air purifier’s price-value ratio based on all other ratings. We considered if the product’s performance and features justified the price or if it might be better suited for purchase when discounted. PHOTO: Health PHOTO: Health Our Experts We consulted with our team of experts, including certified allergists and air quality specialists, to guide our testing process and help us identify the most effective air purifiers for reducing allergens and improving indoor air quality. Paula Olsiewski, PhD, Indoor air-quality expert, Contributing Scholar at the Johns Hopkins Center for Health Security at the Bloomberg School of Public Health Niha Qamar, MD, Allergy and immunology expert, ENT and Allergy Associates Melanie Carver, Chief Mission Officer, Asthma and Allergy Foundation of America (AAFA) Jeffrey Siegel, Professor at the University of Toronto who specializes in air quality and filtration What to Know About Air Purifiers for Allergies Clean Air Delivery Rate To assess how well an air purifier removes allergens like dust, pollen, and smoke, use the Clean Air Delivery Rate (CADR) as a guideline. The higher the CADR rating, the better the air purifier removes contaminants. Dr. Qamar recommends that your air purifier's CADR should be at least two-thirds of the room area in square feet. For example, a CADR of 250 for smoke means that the air purifier can clean the air in a 250-square-foot room of smoke in one hour. Health Room Size and Placement Choose an air purifier designed for your room's specific dimensions; otherwise, it may not work effectively. Most manufacturers provide recommended room sizes in their product descriptions. Dr. Siegel suggests placing air purifiers where you or the person you want to protect spends the most time or near the source you want to control. Don’t put it near the wall or in the corner. Noise Level Air purifiers operate at different noise levels based on fan speed. Low settings produce about 20 to 30 dB, similar to a whisper, ideal for nighttime use. Higher settings range from 50 to 70 dB, similar to conversations, which can be disruptive while effectively circulating air in larger spaces. Many models also have sleep or quiet modes to minimize noise, making them suitable for everyday use. Replacement Filters The cost of replacement filters and the frequency with which they must be replaced varies from one air purifier to the next. Generally, HEPA and carbon filters last between 6 to 12 months, depending on usage. Some devices come with permanent filters that never need to be replaced or washable filters that can be used multiple times. Health More Air Purifiers for Allergies We Tested We also tested these air purifiers, but they didn't make any of our top categories: Ecowell 12" HEPA Air Purifier with LED Display: At 61 dB, this device recorded some of the loudest noise levels while running on a high setting out of the models we tested. It also produced moderate PM2.5 and high TVOC scores after testing.Vornadobaby Purio Nursery Air Purifier AC1-0040-43: At its highest setting, this device was the loudest we tested. It could work as white noise for a baby's sleep, but it lacks features found in other models, despite decent PM2.5 and TVOC reduction.LG PuriCare 360-Degree Single Air Purifier with Clean Booster: It reduced PM2.5 levels by over 80% on both settings and moderately cut VOC levels. Its high air throughput ensures quick and efficient air cleaning. Who We Are Samson McDougall is a journalist, copywriter, editor, and biology graduate. As a writer for Health, he has covered a range of topics from heart monitors and mattresses to toothbrushes and mosquito repellents. Lauren Paige Richeson is an editor at Health, where she plays a crucial role in curating and presenting health-related content. With a strong background in health journalism and a passion for wellness, she engages readers by informing them about important health issues and empowering them to make better lifestyle choices. Through meticulous research and a keen editorial eye, Lauren ensures that the information published is both accurate and accessible. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit 5 Sources Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. US EPA O. The inside story: a guide to indoor air quality Vijayan V, Paramesh H, Salvi S, Dalal AK. Enhancing indoor air quality –The air filter advantage. Lung India. 2015;32(5):473. doi:10.4103/0970-2113.164174 Yoda Y, Tamura K, Adachi S, Otani N, Nakayama SF, Shima M. Effects of the use of air purifier on indoor environment and respiratory system among healthy adults. IJERPH. 2020;17(10):3687. doi:10.3390/ijerph17103687 Chen Renjie, Zhao Ang, Chen Honglei, et al. Cardiopulmonary benefits of reducing indoor particles of outdoor origin. Journal of the American College of Cardiology. 2015;65(21):2279-2287. doi:10.1016/j.jacc.2015.03.553 American Lung Association. Dust mites