# I Filled a Tent With Smoke to Find the Best Air Purifier > Smoke pellets in a sealed tent, a decibel meter, and a month of real apartment air separated the purifiers that work from the ones that just look busy. - Title: I Filled a Tent With Smoke to Find the Best Air Purifier - Summary: Smoke pellets in a sealed tent, a decibel meter, and a month of real apartment air separated the purifiers that work from the ones that just look busy. Buy… - Keywords: air purifiers, hepa, indoor air quality, wildfire smoke, allergies, Filled, Tent, Smoke, Find, Best, Air, Purifier - Source: WIRED — https://wired.com/gallery/best-air-purifiers - Author: Molly Higgins - Published: 2019-07-28T12:00:00+00:00 - Read time: 4 min - Topics: air purifiers, hepa, indoor air quality, wildfire smoke, allergies ## Bad air follows you A decade in Los Angeles and San Francisco meant N95s behind the bar during wildfire season. New York swapped that for bus exhaust, pollen spikes, and smoke drifting down from Canada. > Beneath an eerily yellow sky with smoky, stagnant air, I donned an N95 mask as a bartender ## A gas stove and two cats A tiny apartment, no hood vent, two very furry cats, and a roommate allergic to them. The daily fight is dander and microscopic allergens, not distant fires. ## Smoke pellets in a tent Every unit ran the same gauntlet: a sealed tent, a smoke pellet, auto mode. A timer tracked visual clearing, then an air quality monitor tracked the return to healthy. ## Noise gets measured too A phone decibel meter logged sleep mode, auto mode, and the highest setting. Purifiers can be egregiously loud at full blast, which is how they end up switched off. > air purifiers can be egregiously loud on their most powerful setting ## Then a month of real life Each purifier moved around the apartment for weeks: beside the unventilated gas stove, under the fume-drawing living room window, and next to the litter box. ## The pick for most homes The Coway Airmega Mighty2, $270, cleared the tent and restored healthy air in about four minutes. Quiet, compact, and it needs almost no intervention. ## One filter, twelve months A prefilter catches the big stuff, and a combined carbon and HEPA cartridge handles odors and microscopic particles. That cartridge lasts a year, double the usual. ## It thinks for itself A MegaScan laser reads PM1.0, 2.5, and 10, and the fan adjusts on its own. Three minutes of darkness in the room and it slips into sleep mode. ## Air purifier math Count how many cheap purifiers you will burn through in a decade. That arithmetic is what makes the $1,400 IQAir Atem X, with a 10-year warranty and repair parts, defensible. > I use the term “air purifier math” to consider how many air purifiers you might burn through in the next decade. ## The Atem X blind spot It is sleek, quiet, app-controlled, and sits flush to a wall. But there is no carbon filter, so gases and cooking odors pass straight through. ## For odors and VOCs The Coway Airmega 450 is a 30-inch tower on wheels that glides across a floor. It hits the CDC's five air changes an hour in a 300 to 400 square foot room, quietly. ## Cheap that punches up The Levoit Vital 200S-P, around $190, cleared smoke visually in 30 seconds and hit good air in just over four minutes. On auto it stayed inside the room's own 40 to 45 decibel hum. ## The app is the reason Historical air quality by day and week, filter life, schedules, bad-air alerts, and Alexa or Google voice control. A pet mode alternates fan speeds to pull in fur and dander. ## Three stages inside A washable prefilter, activated carbon, and a HEPA-grade inner filter, behind a U-shaped inlet built to trap floating pet hair. Note that it is HEPA-grade, not true HEPA. ## Bedrooms and small rooms The older Coway Mighty AP-1512HH weighs 12 pounds, tops out at a mild 53 decibels, and covers 368 square feet. The Brondell O2+ Horizon suits 112 square feet but screams at 80 decibels. ## The one that never let smoke in The $1,200 IQAir HealthPro Plus XE stopped the tent from clouding at all. Hazardous readings were back to an AQI of 22 within three minutes, with PM2.5 hovering near 2. > the IQAir purifier never even let the pollutants cloud the tent ## Pets, asthma, wildfire smoke Dreame's FP10 sweeps hair into a removable chamber but took seven minutes to fully clear. AirDoctor's 5500i covers 1,000 square feet at 50 decibels. Rabbit Air's BioGS 2.0 adds a five-year warranty. ## The Shark that failed The BreatheClear Max never auto-engaged in the tent, the smoke refused to clear, and an accidental restart meant nearly five hours before the monitor read healthy again. > it took almost five hours for the monitor to read that it was at a healthy level again ## Don't trust the light Coway's Airmega Halo glowed blue for healthy after 1 minute 45 seconds. An independent monitor said six minutes. Most brands also invert AQI colors, so blue or green rarely means what you think. > an alarming, almost-four-minute discrepancy ## Size it so it can stay quiet AirDoctor's AD4000 hit 100 decibels at full blast, past the CDC's 15-minute exposure limit for workers. Buy enough coverage that the fan never has to reach that setting. > all air purifiers need to be in a space where they can run the fan at the lowest (or reasonably quiet) setting ## Key takeaway Buy for your actual pollutant and room size, run it on auto at a quiet setting, and treat a long warranty as part of the price.