I Filled My Office With Smoke. This GermGuardian Air Purifier Cleared It in Under an Hour.

4 min readAir quality concerns have unfortunately become as much a part of summer as fireworks and backyard barbecues. Wildfires produce a tremendous amount of air pollution, exposing us to fine particulate matter that can cause a range of respiratory issues. And even when this isn’t a concern, you can have allergens, dander, and just stale air to contend with. In fact, the air quality inside your home may even be worse than what you’re breathing outdoors.An air purifier can help reduce airborne contaminants such as smoke, dust, pollen, and particles that may contain bacteria or viruses. But since this is an appliance you’ll be sharing your living space with, you also want a device that’s effective, runs quietly, and doesn’t look ugly while doing it.ProsEffectively removed particles during testingQuiet during everyday useUseful app controls and Auto modeEasy setupConsApp provides limited particle dataAuto mode isn't particularly responsive to odorsTest unit developed a tapping noiseKey SpecsDimensions10.25 x 10.25 x 20.51 in.Weight7.5 lbCoverageUp to 1,680 sq ftCADR230 dust; 250 pollen; 225 smokeFilterHEPA, carbon, fabric pre-filterEnergy Star CertifiedNoWarranty3-year limited GermGuardian says the AirSafe+ XL Smart Air Purifier captures 99.97 percent of allergens down to particles as small as 0.1 microns. The smart app integration aims to make this even more seamless, letting you monitor your air quality, set timers, and know when to replace your filter. After two weeks of testing, I found the GermGuardian to be effective and impressively quiet during everyday use, though a few quirks kept it from being an incontestable recommendation.How I TestedTo test the GermGuardian, I ran it for a week each in two separate rooms of my house: my approximately 90-square-foot office, where I spend much of my day working, and my basement, where I keep my cats' litter boxes. Since the air quality of my home is quite good, I did my best to pollute it by burning incense papers, testing both the limits of the purifier (and my smoke detectors).I then took air quality readings from the GermGuardian every 15 minutes to determine how quickly it brought the air quality in my office back to acceptable levels. I also observed how quietly the GermGuardian ran at both its normal level and at the fan’s highest settings.Easy Setup, Surprisingly Good LooksSetup was refreshingly easy—do you know how many times I’ve received a brand-new air purifier and had to unwrap and install the filter? It’s an unnecessarily fussy step that the GermGuardian thankfully spared me.I installed the app, plugged it in, and let it begin to take readings. The unit itself is tall (about 20 inches high) and fairly slim. A removable fabric sleeve covers the bottom half, doubling as a prefilter and making the purifier look a little less industrial.Katherine TuttleFor comparison, the Germ Guardian is just slightly larger than a typical house plant pot.Effective Air Cleaning, Though Data Lacks SpecificsI primarily kept the GermGuardian on the automatic setting, letting it filter the air when needed. The Aria app displays air quality on a 0-to-500 scale, with readings categorized as Good (0 to 100), Average (101 to 300), or Poor (301 to 500). However, GermGuardian doesn't specify in the app what type of particulate matter the sensor is measuring.To test both the GermGuardian’s air purification and odor control abilities, I let the machine take a reading of the air quality in my room, with all windows shut and the HVAC system turned off. I then lit an incense paper, let it burn, then turned the unit on. The room started at a reading of 29, spiked to 368 immediately after I burned the incense, and dropped to 71 after 45 minutes of running the purifier on auto mode.In my basement, however, Auto mode didn't react aggressively to litter-box odors, so I found myself manually increasing the fan speed instead.Quiet Enough for an Office or BedroomThe first real test was how quietly it would run in my approximately 90-square-foot home office. The GermGuardian is rated to clean the air every 12.5 minutes in a 348-square-foot room, or once per hour in a 1,680-plus-square-foot medium-to-large room.GermGuardian rates the purifier as low as 22 decibels. In my office, my NIOSH sound meter app registered around 40 decibels at a fan speed of 4, though it’s important to note that my home's ambient noise and phone microphone mean that this shouldn't be treated as a laboratory measurement. At that level, it faded easily into the background while I worked.However, I also wanted to test it at its highest setting. At fan speed 10, I measured roughly 65 decibels, loud enough that I wouldn't want it running beside me while working or watching TV.Katherine TuttleThe Germ Guardian has a clear display that shows the quality of the air on a scale from 0–500.Smart Features Make It Easy to Live WithThis particular model features an activated carbon filter for controlling odors and an air quality monitor sensor. The top-mounted controls cover the essentials, including Auto and Sleep modes, 10 fan speeds, filter-life indicators, and a display-off setting.This model is also WiFi-enabled, and you can control all of these functions and monitor your air quality via the Aria app. The filter needs to be replaced approximately every six to eight months (refills cost around $50 at the time of writing).Katherine TuttleYou can view the air quality in your home, adjust the fan speed, and more from within the app.My Unit Developed an Annoying Tapping NoiseAfter about three days, my test unit developed a repetitive tapping sound. I removed and reseated the filter but couldn’t identify or correct the source of the noise, which seemed to be related to the fan speed.This did not affect the unit’s performance, but it did become irritating. I can't say whether this is a widespread issue or a defect specific to my unit, but it’s something worth noting.Final ThoughtsFor an air purifier that effectively cleans the air in your home while staying quiet and relatively hands-off, the GermGuardian is a solid choice. Its quiet operation and app connectivity make it a good choice for an office or other spaces where noise is an issue. However, if you’re someone who prefers detailed particulate matter readings or a high-powered automatic response to odors, you may wish to look elsewhere.The tapping noise that developed in my test unit also gave me pause. It does make me question the unit’s long-term reliability, though I can't truthfully say if the problem is unique to the unit I tested or not.Shop the GermGuardian AirSafe+ XL Smart Air PurifierOther Air Purifiers We LoveCoway Airmega Mighty2 Air PurifierClorox Home Appliances Air PurifierNow 14% OffLevoit Vital 200S-P Air Purifier