Fresh Air: Best Air Quality Monitors of 2021

HYVQDNM’s home air quality monitor, unlike its seven-letter company name, is simple and easy to read. It measures six common household air pollutants and collates information into a “mean value” on its blue-and-white LCD screen. It’s easy to move around your house as needed; its size is right between a phone you’d call a brick and an actual brick, and its USB-rechargeable battery lasts about a day. It fulfilled my expectations on testing: I could check it quickly as I walked by, I didn’t have to worry about an associated app, and it indicated pollution when I put it in obviously polluted environments.

The HYVQDNM measures CO, CO2, HCHO, TVOC, PM10, and PM2.5. It does not measure radon, another common indoor air pollutant that’s considered important. The monitor displays information for each pollutant on its screen, refreshing every second or so. It calculates a “mean value” and indicates pollution level on a four-tier visual scale ranging from green to red. An included booklet advises users on toxicity levels and proper use (often in amusing broken English).

I took the HYVQDNM home air quality monitor out of the box, pushed the power button, and it got right to work. At first, it read nearly off-the-scale CO2 pollution on my desk. Referring to the manual, I saw the monitor requires a several-hour calibration period. Sure enough, by that evening the noxious gas reading had leveled off and my desktop air quality was “green.”

The unit gave me no surprises for a few days, so I decided to put it to the test. I have one of those toilets that has its own room, which is also (unfortunately) the only good place for my cat’s litter box. (Please don’t judge). I put the HYVQDNM inside and closed the door. Sure enough, an hour later it showed elevated readings in many categories and a red indicator.

Though I found the kickstand flimsy, the HYVQDNM air quality monitor functioned uneventfully and met my utilitarian expectations at MSRP $96. Read the in-depth review here.

The Airthings Wave Plus delivers real-time and historical app-based IAQ data. The smart home device reads six IAQ metrics including radon levels. For a quick analysis, users can simply pass their hand in front of the smoke-detector-like puck to activate the “glow ring,” which gives an instant green/yellow/red IAQ reading. I tested the Wave Plus and found it delivered on its basic functions. However, the glow ring function proved useless to me and the device took a long time to calibrate.

The Airthings Wave Plus measures indoor air for Rn, TVOC, CO2, humidity, temperature, and barometric pressure. Radon (Rn) is, decisively, the centerpiece of the suite. Radon is the gas released by the natural decay of uranium — so, it’s radioactive. Furthermore, every home is generally considered to have some concentration of it, because it’s in soil, water, and natural gas. At high levels, it’s dangerous.

Happily, my apartment in the Las Vegas valley clocked low radon levels, according to Wave Plus. In fact, it measured each pollutant it measured at consistently low to moderate levels, which I nonchalantly tracked with the app.

Unfortunately, my testing time was limited by the monitor’s long calibration period — seven days. That, plus heavily delayed shipping, meant I only had a few days to test the monitor at full capability as of this writing. During calibration, the monitor still reads data and interacts with the app. But I still hadn’t unlocked secondary app features like the free radon report.

My only real gripe with the Airthings Wave Plus was that the glow ring indicator, in my specific case, meant absolutely nothing. Every time I waved my hand in front of it, it lit up red. Why? Because, here in the desert, my air falls into the “unhealthy” range for humidity. I know the air’s dry, and I don’t care. Even if I did, is dry air actually unhealthy? At some level, it’s pretty intuitive: you’re in the desert, drink more water.

Then again, Now I’m thinking about hydration. It’s good to stay hydrated. Am I dehydrated right now? I should go pour myself some water….

The Airthings Wave Plus seems like a good purchase for anyone interested in closely monitoring radon levels, who values a smart device with good app connectivity. For those more interested in keeping casual tabs on their IAQ for personal reference, it might be overkill, especially at $200 MSRP. Read the in-depth review here.

Curiously-titled Four Uncles delivers a cost-effective, laser-operated indoor air quality monitor for MSRP $69. The monitor measures levels of seven different pollutants. A low-noise fan draws air into the unit, where a laser reads it for transparency and refraction. Then, five different sensors decode the information. Finally, an LCD screen displays real-time values for five common indoor air pollutants. Using Four Uncles is as simple as that — wait, what? Using the Four Uncles indoor air quality monitor is as simple as that.

It’s compact, at about 5.5” long, and powered by a USB rechargeable lithium-ion battery. Reviews indicate around eight hours of battery life. Four Uncles recommends the device for use in any common indoor space, as well as in the backyard, hotel room, or even the “cloak room” (their words not mine).

Awair helps users monitor their indoor air quality with the Element monitor and Awair app. The element tracks CO2, TVOC, and PM2.5, plus temperature and humidity, and feeds the information to the highly-capable associated app. The Element also features smart assistant integrations.

The Awair app is the centerpiece of the smart air quality monitor kit. It displays IAQ data in real-time and stores it as history. It delivers actionable feedback based on ongoing measurements — information on which pollutants are present where, and suggestions for remediation. The app even lets users customize feedback to help with various goals like improving sleep and reducing allergies. As well, the app can act as a hub for multiple Element devices placed in multiple rooms (similar to the Google Home app).

Temtop’s M10 is an air quality monitor with a large, clear display for easy reading of four pollutants. It adds an AQI measurement. The discreet unit is ready for any end table, desk, nightstand, or even vehicle.

The Temtop M10 is intentionally rudimentary in form and function. It reads PM2.5 and PM10, HCHO and TVOC, and delivers AQI. It displays levels for each pollutant one at a time on its pronounced screen. Simply push the top button to toggle between readings. The screen shows battery life and a green/yellow/red light to indicate AQI.

The IQAir AirVisual Pro sets itself apart from other air quality monitors with an app geared toward sharing air quality information. Other differentiation points include an industrial-grade CO2 sensor, a unique display including both indoor and outdoor air quality information, and a user ability to program commands based on readings.

Besides reading CO2 and PM2.5, the AirVisual Pro displays AQI and gives humidity, temperature, and even weather and air quality forecasts. IQAir does its best to ensure accuracy with its choice to use an industrial-grade CO2 sensor. The display is detailed and informative, and just goofy enough to be endearing with its bright colors and cartoon faces. 

The miniscule BREATHE personal air quality monitor measures real-time AQI and PM2.5 for on-the-go monitoring. BREATHE designs the little unit to be easy to read, straightforward, and portable.

Yes, the tiny unit measures only PM2.5 and generates AQI. This means it’s a rough-estimate instrument, in no way designed for data analysis like some of the intensive, app-connected devices in this guide. Instead, BREATHE says the monitor needs virtually no calibration time, and that you can carry it around on your wrist for a snapshot of the air quality right where you stand. It has a touchscreen and its battery reportedly lasts several hours.

With its sleek pill shape, the Huma-i Hi-150 is one of the most portable air quality monitors you can buy. It measures four common pollutants, plus temperature and humidity, and displays AQI.

An OLED display toggles between graph or icon view depending on the user’s preference and a green/yellow/red indicator light gives quick information on current air quality. Huma-i recommends the Hi-150 for indoor or outdoor use. It detects CO2, PM2.5 and PM10, and TVOC for a balanced air pollution measurement. The display powers down after ten minutes to save battery, but it’s unclear how long the battery lasts between charges.

EG’s air quality tester is a professional-grade device with specialized sensors, specific calibration notes, and a scientific approach to air quality measurement. Its value is based on a lot of terminology and concepts that are beyond the scope of this guide, and my ability to succinctly explain them (what is the role of air convection in an IAQ? What is the value of an electrochemical formaldehyde sensor?) but EG has a midwest-based technical staff including a chemist to answer any questions.

EG also emails customers a 20+ page eBook about gas and air quality hazards with their purchase. Extensive tips on using the monitor help interpret seemingly erroneous data and minimize misreads. Though it features a simple screen and utilitarian appearance, it stores historical data in charts.