The air-quality readings it takes are stored and viewable in the app, giving you a long-term picture of your homes air quality. Install your purifier at least 18 inches from a wall and any furniture, ideally near the midpoint of the room youre using it in. We have a separate section about them called The worst air purifiers weve ever tested. Setting aside the dubiousness of that claim, even low levels of ozone can be harmful (PDF).
However, though the fires are long since over, we have continued to see occasional complaints, and when we asked Coway for a further explanation in February 2021, representatives wrote: The filter is manufactured by processing various polymer materials (polypropylene, polyester, polyethylene, etc. Both models also draw far more power than their supposed equivalents among our picks, and both cost the same or more up front. The Blueair Blue Pure 311 Auto is similar in capabilities to the Coway AP-1512HH Mighty and the two Winix models. The Blueair Blue Pure 211+ is our choice among air purifiers for large spaces of up to 650 square feet, especially when the space involves open floor plans or high ceilings. In our 2019 test, in just 30 minutes the Blue Pure 211+ reduced a heavy load of 0.3-micron smoke particles by 99.3% and 98.4% on high and quiet/medium, respectively, with filters that had seen eight months of 24/7 use. In 2018, we declared the Blue Pure 211+ the stiffest competition weve found for the Coway AP-1512HH Mighty, our long-standing top choice for general use. But its only slightly more powerful than our top pick, the Coway AP-1512HH Mighty, yet costs $200 more. And it has other features we like, including notably quiet performance, terrific energy efficiency, and a control panel that automatically dims after you adjust the settings. The Hathaspace Smart True HEPA Air Purifier has solid reviews and typically costs a bit less than the Coway AP-1512HH Mighty. That means it can clean the combined living areas of many open-floor-plan homes. We have not tested the Dyson Pure Hot+Cool HP06 Cryptomic purifier, but we did speak at length with a Dyson engineer and representative about it. But in our tests it performed significantly worse, achieving just 77.4% and 55.1% reduction on its highest and medium (speed 6) settings, respectively. In raw performance during our 30-minute tests in fall 2020, the Winix 5500-2 slightly outperformed the Coway AP-1512HH Mighty. Compared with tower-style purifiers weve tested, which have smaller footprints but are much taller, and compared with our large-space and VOC picks, which are monolithic, the Coway AP-1512HH Mightyespecially the white versiontakes up less visual space. The NAD and NARB cases made clear that this was an understatement: All of Molekules quantified claims about the Airs performance, all of its claims about the technologys superiority to HEPA, all of its customer and doctor testimonials about the ability of the Airs filter to reduce asthma and allergy symptoms, and many of its claims to have been independently tested were deemed unsupported. Its an equally solid choice in terms of performance. Well, duh: Any air that passes through a HEPA or medium-MERV filter will be virtually particulate free. At that fan speed, however, its far too loud for anyone to make conversation or watch TV nearby. Blueair recommends replacing the filter every six months or so. Following that schedule, you spend $80 a year on replacements versus about $50 or less for the Coway Mighty and the Winix machines. Worse, manufacturers calculate their ratings in different ways, often resulting in massively inflated square-footage claims. As such, both PECO and PCO are completely distinct from HEPA filtration, which physically captures most airborne particles but does not capture VOCs or other molecular-scale pollutants. The two machines are similarly quiet, with the Airmega 400 registering 40 decibels on its quiet/high-medium setting and the Blue Pure 211+ measuring at 43 decibels on medium. The Blueair Blue Pure 311 Auto is another stellar purifier. This purifier was also pricey to buy and to run at the time of our research. Read more in How we picked. The Vesync app provides basic but useful controls: You can set timers, adjust the fan settings, program the machine for optimal operation in different-size rooms, turn the machine and its display on and off, and monitor the air qualityalthough in testing, we found its AQI (air-quality index) reading consistently lower than the local EPA readings as reported in the AirNow app that we recommend. 
It comes only in dark gray, lacks Wi-Fi connectivity, and uses a one-year VOC filter in contrast to the AM90s three-month filters. It was an exceptional performer in our testing, and its quiet and attractive to boot. The Molekule Airs comparable costs total about $1,350. The Coway Airmega 200M is made by the same company as the AP-1512HH Mighty and is virtually identical to that model in every important respect, namely the controls, noise, and performance. On the medium setting, it draws just 8.1 watts, so running it 24/7 on that setting consumes just 71 kilowatts annually. We tested the Shark Air Purifier 6, a large-space machine; the company also has a less powerful model, the Shark Air Purifier 4. Most air purifiers arrive with the filters installedbut also sealed in plastic wrappers. Cisno, Airthereal, iTvanila, Secura. (Human hair, for reference, is usually between 20 and 180 microns across.) Our journalists combine independent research with (occasionally) over-the-top testing to save people time, energy and money when making buying decisions. The NK100 also has lower specs than the Coway and typically costs a bit more. Tim Heffernan, senior staff writer, tested from 2020 to 2022 (and ongoing). The Frnuftig disappointed, even when we considered that the test room was larger than the machine is meant for, as it removed just 85.2% of 3-micron particles in 30 minutes on high and 73.6% in 30 minutes on medium. Ionizers produce a small amount of ozone as a by-product, but as laid out by the strict California Air Resources Board, none of our picks with an ionizing function exceed the limit of 0.050 parts per million (50 parts per billion). Interestingly, those numbers closely mirror our results on the Auto setting with the PECO system turned on, suggesting the possibility that the Molekule Air mostly relies on its physical prefilter, not its proprietary PECO mechanism, to eliminate particulates. He has anchored our unequaled coverage of air purifiers and water filters since 2015. As the CDC writes: The best way to prevent illness is to avoid being exposed to this virus..
Dyson calls the Pure Cool Me BP01 a personal purifying fanits designed to deliver a focused stream of air onto a persons face from a bedside table or an office deskand does not consider it a whole-room purifier, so we didnt test it. We attribute the Minis superiority over the Air to its much bigger physical prefilter: Its about five times larger by area than the Airs. Since 2017, he has conducted extensive real-world testing of air purifiers in his New York City apartment and in Wirecutters New York and Los Angeles offices. We still prefer the Mighty for its lower energy consumption, smaller visual footprint, display-shutoff feature, and more attractive look, but its a close race. They are especially good at rapidly filtering out the most common airborne allergens, including dust and pollen; mold, mildew, and fungal spores; pet dander; dust mites and their excrement; soot from automobiles; and tobacco, marijuana, and wildfire smoke. AirDoctor sells an expensive purifier with a filter that it markets as UltraHEPA, claiming that the filter traps particles 100 times smaller than what HEPA can capture. Given its high up-front cost and relatively weak performance, we cant recommend it. Tim tests each purifier twice: once for 30 minutes with the machine on its highest sub-50-decibel setting (about the upper limit of what we can consider comfortable for conversation, TV, or sleep) and once for 30 minutes with the machine on its absolute highest setting regardless of noise output. Its large and visually intrusive, too, consisting of a black tower almost 2 feet tall, 18 inches deep, and 10 inches wide. You should do the same if you try this hack. The Coway Mighty has a number of other qualities that make it easy to live withand thats important for a device that typically runs 24 hours a day and lives in a bedroom, playroom, or living room. Right? Heres a list of what to do: Remove the wrappers. Many employ a second filter, containing adsorbent compounds such as activated carbon, to capture gases and odors (volatile organic compounds, or VOCs)but we have not found these to be very effective. For optimal performance, vacuum, wipe down, or rinse off the prefilter (it looks like a window screen or plastic netting) every month or so. When we found the CADR numbers in the manuals, we were alarmed. When it comes to handling particulate pollution, the HM400 is a solid performer, reducing particulates to less than 20% of starting levels after 30 minutes on high in our 2017 real-world test (fourth best in our high-setting test) and to 50% (joint third best) on low. The solution is to make the filter dense enough that it has a sufficient amount of fibers to capture most of the 0.3-micron particles. 
We calculate a standardized ACH for each machine in hypothetical rooms of 150, 350, and 500 square feet. The Winix 5500-2 is an exceptional performer on particulates, capturing 99.9% of the smoke in our test room in just 30 minutes on high and 97.2% on its medium-high setting, where it emits an easy-to-live-with 40 decibels. Other criteria also matter. For comparison, the Coway Mighty measured 39 decibels on medium and 31 decibels (nearly inaudible) on low. The huge and exceptionally powerful Medify MA-112 has the highest CADR rating weve ever seen: 950. Yes, we have tested the Molekule Air (the flagship model) and the Molekule Air Mini. The differences are insignificant in and of themselves, and from our years of testing we know that all the filters would reduce particulate levels to nearly zero over the course of a few hours. The Philips 1000 Series purifiers cost more and have similar or weaker specs compared with our Coway top pick. If your main concern is air quality, you can certainly find purifiers as powerfullike the Coway AP-1512HH, Winix AM90, and Blueair Blue Pure 311 Autofor far less. The Blueair Blue Pure 211+ is not true HEPA, but it has undergone CADR testing, which in some ways is a more rigorous standard. To remove allergens such as pet hair and pollen, you need a vacuum cleaner or dust mop. The Core 300 is easy to live with for a few reasons.
And our past tests have indicated that the Coway Mighty, running on high for an hour, can reduce particulate pollution by nearly 100% in a typical bedroom and then keep it there permanently on medium. The purifiers themselves sat at the midpoint of the opposite wall of the room, 2 feet from the wall, with no obstacles near their air intakes and outlets. If you simply need to remove particulates from your air in a large space, the Blue Pure 211+ is easier to live withits quieter, smaller, and better looking, which is why its our main pick for large spaces. But to qualify as great, an air purifier needs to be powerful enough to clean the air in a large living room or playroom, quiet and dark enough for you to sleep near it in a bedroom, and inexpensive enough that its reasonable to have several spread throughout your home. This model typically costs only slightly less than our top pick for large spaces, the Blueair Blue Pure 211+, which is a more powerful, more attractive, and quieter machine. The Round Console was also weaker on specs and higher priced than the Coway, at $300. Replacing the filters (an annual task for the HEPA filter, semiannual for the VOC filter) is easy: You simply unclip the front cover from the unit and pull the pre-, VOC, and HEPA filters out using their handy pull tabs.