Smart Air

Smart Air is a social enterprise and certified B-Corp that puts 100% of its profits into helping more people breathe clean air. We have previously reviewed the Smart Air S, Smart Air Blast Mini and their portable QT3, and we are big fans of their ethos and the information that Smart Air shares with the world. 

Back in 2022, we accepted Smart Air’s offer to lend us an SA600 so we could review it and return it to them afterwards. Normally, we only review air purifiers that we bought with our own money to avoid biases, so when manufacturers ask us to review their products, I make it clear that we will be open and honest with our readers. Most companies ghost me when I say this, but Smart Air was happy to let us say exactly what we thought.

The problem with the arrangement was that we only had the SA600 at home for two weeks, which gave just us enough time to run our usual tests but didn’t allow us to perform long-term experiments. But in 2024, Smart Air released an updated version of the SA600 with five fan speeds (versus the three we saw in the first model we reviewed, so we decided to buy this new and updated SA600 so we could update our review.

Today, I’m sharing with you the result of months of testing the Smart Air SA600 in our home to see how it performs in the real world.

The pros and cons of the Smart Air SA600

A summary of our top-level findings after testing this air purifier following our methodology.

The best feature: three out of its five fan speeds generate less than 45dB of noise

Not only that, but when running at these lower fan speeds, the SA600 offers excellent air cleaning performance.

In 2022, we reviewed the first version of the SA600 and tested its three fan speeds. The SA600 v1 offered good air cleaning performance when running at its top speed (56 db) but this power didn’t translate to its sub-45dB speeds. With the v2 of the SA600, Smart Air changed that.

The SA600 comes with five fan speeds, which range from 35 and 56 decibels:

	SPEED 1	SPEED 2	SPEED 3	SPEED 4	SPEED 5
NOISE LEVEL (from 3ft away)	35.2 dBA	37.2 dBA	41.5 dBA	46.1 dBA	56.7 dBA

I tested the SA600 running at speeds 3, 4 and 5 inside our 728-cubic-feet test room, using our PurpleAir Zen sensor to track how long it took for the air purifier to reach PM1 zero after we burnt an incense stick:

• SPEED 5: 24 minutes. This is the same time it took for the Coway Airmega 250S, the RabbitAir A3 and the Winix 5510 to reach PM1 zero.
• SPEED 4: 36 minutes. Faster than the Levoit Vital 100S (37 minutes), the Mila (38 minutes) and the Coway Airmega 150 (38 minutes) at top speed.
• SPEED 3: 46 minutes. Faster than the Core 300S (45 minutes), the PuroAir 240 (51 minutes) and the Molekule Air Mini+ (61 minutes) at top speed.

This makes the SA600 an excellent choice for spaces that need quiet operation without sacrificing on air cleaning performance, such as offices, classrooms, bedrooms and TV rooms. However, if quiet is important to you, make sure to also research PC fan-powered air purifiers like the Luggable XL-7 from CleanAirKits.

Design, controls and features

The SA600 has two filters on each side of the unit to capture pollutants and VOCs from both sides of the device.

I like the simplicity of the SA600’s design and Smart Air’s decision to use matte plastic, as it far less prone to smudges and fingerprints compared to the shiny plastic we see in so many other devices like the Coway AP-1512hh or the PuroAir 400.

This is a mid-sized air purifier, that has similar dimensions and will take up as much floor space as devices like the Levoit Vital 200S and the Coway Airmega 150.

However, unlike the Vital 200S or the Airmega 150, the SA600 pulls air from both sides of the device and has two sets of filters through it’s dual inlets.

That means you get one H13 HEPA filter and one activated carbon filter on the left side of the unit, and then another H13 HEPA + carbon combo on the right side. The SA600 also comes with a removable pre-filter at each side:

Now, this use of additional filters means you will have two pre-filters to keep clean and you will need to replace double the number of HEPA and carbon filters each year. I will break down the annual running costs further down in the review, including calculations for filter replacement and energy costs.

Like with the other devices we have reviewed from Smart Air, the controls are straightforward with simple operation. You get just four buttons: one to cycle between the five fan speeds, a lock to prevent the settings from being changed, a filter replacement indicator, and a power on/off button.

There are three lights to the left of the fan speed button where you will be able to see what speed the SA600 has been set to, with speeds over Speed 3 showing with two lights:

Like other Smart Air air purifiers, the SA600 doesn’t offer smart modes (such as auto mode or sleep mode) and it doesn’t come with a smartphone app to control the unit from afar. That being said, you can use this device with any type of smart plug to set routines as part of your smart home hub.

Although fairly commonplace in today’s appliances, the child lock and the filter reset light make this the ‘smartest’ model from Smart Air. These are quality-of-life features that won’t necessarily impact the air cleaning performance of the air purifier as much as the four filters will, but that users will appreciate in their daily lives.

To wrap up this section, let me tell you about a unique feature of the SA600 that I haven’t seen in any other air purifiers I have tested: the ‘Do Not Disturb’ mode. Without the need of you pressing any button, the SA600 turns off all control lights automatically if you don’t touch the buttons for three minutes. This makes the SA600 a great choice for nursery rooms, bedrooms and TV rooms, where LED lights can become an unwanted distraction.

Filtration technology

Two HEPA H13 filters and two activated carbon filters supercharge the SA600’s air cleaning performance, by cleaning air from both sides of the device.

In 2023, Dyson made a complaint to the BBB National Programs National Advertising Division (NAD) about Levoit’s use of ‘HEPA’ in their marketing. The complaint forced Levoit to refrain from saying their main filtration was powered by HEPA 13 filters because it wasn’t true. 

With that in mind, we were glad to see that the HEPA filters for the SA600 have been third-party lab tested as per AHAM AC-1-2002, so we can be confident they are genuine H13 HEPA Filters

The best thing is that the SA600 comes with two of these pelleted activated carbon filters, meaning that you will have A LOT more carbon to absorb unwanted odors, gasses and VOCs than the average air purifier.

As with other Smart Air air purifiers, the fan of the SA600 is a powerful little beast, which helped this unit clear the air from incense smoke in our test room in just 24 minutes.

When you change the filter in your Smart Air SA600, you’ll find that the process is simple. Here is a video taking you step by step:

Air cleaning performance

The Smart Air SA600 cleared our test room in 24 minutes — the same result achieved by the Coway Airmega 250S, but a few minutes faster than the Winix 5510.

The CADR report of the SA600 stated that this devices has a dust CADR of 287 cfm, so I expected it to take between 23-25 minutes to clean the air based on our data from every other air cleaner we’ve reviewed to date.

We tested the SA600 in the same 728-cubic-feet room where we tested nearly 100 different air purifier models since 2020. By testing every device in the same room doing the same job of removing incense smoke, we can confidently compare performance across devices.

The Smart Air SA600 cleared our test room of PM1 particles in 24 minutes, when running at its highest fan speed:

The Smart Air SA600 is much faster than the more expensive Mila (38 minutes) but slower than the Vital 200S (23 minutes). See how the performance of this device compared to other similarly-priced devices:

So, the real-world performance of the Smart Air SA600 matched up to the lab-reported CADR scores. This was great to see, considering that this air purifier uses two activated carbon filters that are likely to reduce the airflow for particle removal.

Based on a CADR of 287 cfm, this device could provide five air changes per hour in rooms as large as 430 sq. ft. You can use our CADR calculator to see how many air changes it will offer in your space.

Noise levels test results

While air cleaning performance is very important when shopping for an air purifier, you also need to be mindful of how loud it is. The reality is that if an air purifier is too long, it will end up being turned off eventually. 

That is why we use a sound level monitor to gather comparable data on noise level generation by recording how much sound in decibels is generated by the air purifier from three (3) feet away in the same corner of our basement studio.

In the table below, we share how much noise is generated by the SmartAir SA600 at each of its five fan speeds:

FAN SPEED	SOUND LEVELS IN DECIBELS
Speed 1	35.2 dBA
Speed 2	37.2 dBA
Speed 3	41.5 dBA
Speed 4	46.1 dBA
Speed 5	56.7 dBA

Be aware our background noise is very similar to what we got for speed 1, so the actual result is likely to be much quieter.

When compared to other air purifiers with similar performance, the SA600 is a little quieter than many of the HEPA retail devices we have but louder than the PC fan powered devices. 

The benefit of high CADR air purifiers is that you can use them at lower, quieter fan speeds, while still benefitting from good air cleaning performance. That is why we always re-test the particle removal performance of our air purifiers when running at sub-45dB fan speeds, which is the limit set by Clean Air Stars for offices and classrooms.

So, we ran the same incense smoke test in the same 728 cubic feet space with the Smart Air SA600 sunning at both speed 3 (41.5 dBA) and speed 4 (46.1 dBA).

Of course, when accounting for lower sound levels, the PC fan-powered devices offer a more powerful air cleaning performance at whisper quiet operation compared to the Smart Air SA600 and all the other HEPA retail air purifiers in the bunch.

But have a listen for yourself, as I know that sound can be subjective:

Long-term running costs

Running a Smart Air SA600 will cost you $131.08 per year, combining energy consumption costs and filter replacement prices.

As part of our reviews, we always calculate how much you can expect to spend on a yearly basis, assuming you are running the device 24/7 all year round utilizing our own energy consumption data and the manufacturer’s filter lifespan data.

1. Electricity costs = $59.98 per year

We used our power monitor to record the energy consumption of the SA600 at each fan speed and on standby mode:

FAN SPEED	ENERGY CONSUMPTION IN WATTS
Standby	0.1 watts
Speed 1	2.4 watts
Speed 2	4.3 watts
Speed 3	7.1 watts
Speed 4	12.9 watts
Speed 5	53.8 watts

If you had to leave the SA600 running 24/7 at full speed, it would cost $59.98 in energy costs for a year, and now we can compare the energy costs to other devices we have tested.

Smart Air uses a very efficient fan with its SA600 to pull in a lot of air without requiring much electricity. As you can see from the table above, it benchmarks very well against the other devices, even when running at lower fan speeds.

2. Filter costs = $71.32 per year

On the U.S. website of Smart Air, they recommend replacing the four filters for the SA600 every 18 months:

As of January 2025, the OEM H13 HEPA filters cost $57.99 (2-pack) and the activated carbon filters cost $48.99 (2-pack). This leads to an estimated filter replacement cost of $71.32 per year, which together with the energy consumption costs, will lead to an estimated yearly running cost of $131.08.

You can find generic filters for the SA600 on Amazon that will save you money, but they won’t offer the same performance as they will vary depending on the grade of HEPA or the amount of carbon. For example, when testing generic filters from PUREBURG, we found that they tend to pack more activated carbon than official filters, which restricts airflow and affects particle removal performance.

A benefit of choosing official Smart Air filters is that you know you’re buying third-party lab-tested H13 HEPA filters.

At this point of the review, we can calculate the long-term maintenance costs you need to budget for if you decide to get yourself a Smart Air SA600. See how they compare to other mid-tier air purifiers in the same price range:

As you can see from the table, the Smart Air SA600 will cost you more to run compared to other popular air purifiers, such as the AirFanta 3Pro or the Levoit Vital 200S. But overall, the costs are aligned with what is expected from a medium-sized air purifier — quite an achievement considering the use of four filters!

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Bottom line: Is the Smart Air SA600 worth it?

A mid-sized air purifier that offers 360-degree air cleaning, with performance that rivals popular units from Winix and Levoit.

I’ve received many emails from people who prefer to avoid smart functionalities and phone connectivity. If that is you, then the Smart Air SA600 should be at the top of your list for consideration.

The SA600 has no ionizer function, Bluetooth or WIFI, so it is the perfect choice for those looking for a non-smart air purifier that will clean the air without chemical by-products or unnecessary (and costly) extras.

Now, if you’re set on using an app to control your air purifier, this is likely not the right device for you. However, it is worth considering that you can use a smart plug to connect the SA600 to your smart home hub.

I am a huge fan of features such as having the LED lights on the control panel switch off automatically, or the device’s ability to come back on after a power cut. At home, the SA600 found a spot in our TV room, where it runs 24/7 at speed 4 and cleans the air quietly without distracting lights or sounds.

The two inlets and two sets of filters will lead to higher filter replacement costs, but I appreciate that the filters are separated (compared to the bonded designs from Levoit) as it allows you to use the device without carbon filter, if you don’t need it.

Not feeling the Smart Air SA600? If you’re looking for the most powerful air purifier you can get for less than $200, then check out the AirFanta 3Pro or the Winix 5500-2. If smart functions are a must, have a look at the Coway Airmega 250S pr the the Levoit Vital 200S. Now, if you want a powerful yet whisper-quiet air purifier, then make sure to read my review of the PC fan-powered beast that is the Luggable XL-7.

If you have a space smaller than 190 sq. ft. but you like what Smart Air has to offer, then you should look into the Smart Air S instead. Lastly, if you have a space larger than 675 sq. ft., then read up on the Smart Air Blast Mini, as the SA600 will be too underpowered for a large room.

We calculated yearly costs associated with running the Smart Air SA600 24 hours a day, 365 days per year using the appliance calculator from the U.S. Department of Energy as of January 2025.

The creators of the Smart Air Sqair have an interesting backstory.

Back in 2013, the founder of Smart Air (Thomas) was working on his PhD in Beijing and, affected by the terrible outdoor pollution in the area, he looked into buying an air purifier. He was shocked when he saw how much air purifiers were retailing for. Instead of buying a pricey device, he created his own DIY purifier using just a fan and a filter. 

Realizing the potential, Thomas got together with some friends to start his own company focusing on no-nonsense, affordable air purifier DIY kids: a HEPA filter, a box fan and a strap to tie it all together. Smart Air also started to host workshops all over Beijing, showing attendees how to build their own DIY air purifiers.

Since then, they have perfected their HEPA filters and started developing their own air purifier models. Their main goal remains the same from day one: excellent air cleaning performance without the high price tag that most models come with.

I like sharing this story whenever I discuss Smart Air because I think their ethos is remarkable and rare in this day and age. Their mission is one of the reasons why so many consumers are die-hard fans of Smart Air, and you will often find them recommending the Blast Mini or the SA600 to others on social media platforms.

This Smart Air Sqair air purifier only reached the U.S. in 2020. It is Smart Air’s response to small units like the Levoit Core 300 or the Winix A230.

As with all the air purifiers we review here at HouseFresh, we bought the Sqair with our own money to ensure we can be unbiased and completely transparent about what it’s like to have this device in our home. But, of course, we didn’t stop there.

We put the Smart Air Sqair to the test, completing a series of experiments to assess its particle removal capabilities, its energy consumption levels and the noise it generates. You can read more about each test below.

It is worth clarifying that this review was written AFTER we conducted all these tests. You can rest assured I didn’t just grab some numbers off an Amazon listing or Smart Air’s website like most other review sites would.

Right, enough with the intro.

The lowdown on the Smart Air Sqair

These are my main pros and cons suitable for even the lightest of skim readers:

The best Smart Air Sqair feature: it is compact and stylish yet powerful

Excellent air cleaning speed that will look good in your home.

The Smart Air Sqair hides a powerful motor that allows it to move air through the filters at the same speed as much larger (and bulkier) air purifiers.

I will walk you through our particle removal test later down in the review, but let me mention here how the Sqair completed the test 10 full minutes faster than the much more expensive Mila and 15 minutes faster than the popular Levoit Core 300.

It truly surprised me with its air cleaning power because it looks like a small stool. I can’t begin to understand how Smart Air managed to fit in such a powerful motor inside this cute little thing.

Elegant design that will stand out for the right reasons

“Oh wow… This one is cute!” was the first thing my wife said when the Smart Air Sqair arrived.

My wife is not normally so positive about the many air purifiers I bring to our home, but she immediately fell in love with the design of the Smart Air Sqair. This might not seem like an important point (and it’s definitely subjective), but she spends a lot of time choosing furniture and décor for the house, so she is a tough critic.

Another element she liked was the lack of lights on the control panel. This makes the Sqair a great option for a bedroom, as it won’t disturb your sleep — this is where we have kept this air purifier since the moment I finished running all the tests:

But it’s not just about this air purifier fitting into a trendy home.

Another design aspect worth mentioning is that the Smart Air Sqair is a fairly small unit. It doesn’t take up too much space and could easily be placed in small rooms or tight spaces.

You can see here how small it is compared to the Levoit LV-PUR131 (which has the same size of units such as the Levoit Vital 200S, the Winix C545 and the Coway Airmega 150) and the dirty laundry basket in our room.

Undoubtedly, this little unit looks a hell of a lot better than your “normal” air purifier. Its cute, short body and Beachwood legs blend into the room instead of looking like something you would find in a science lab.

Speaking of the legs, you will find them packed separately inside the box and must be screwed on before switching the unit as you would with the legs of an IKEA chair:

I experienced one build quality issue when screwing the legs: one of the screws had become loose, so I had to re-screw it before securing the final leg. It’s definitely a minor thing, but I’m mentioning it here to make the Smart Air team aware of it.

The control panel of the Sqair is incredibly straightforward. You get three fan speed settings and can switch between them with a giant dial that sits at the top of the device. That’s as simple as it gets!

Now, if you are looking for smart features, this is not the right air purifier for you.

I personally like the simplicity, but I also appreciate that there are cases where having smart features such as auto-mode makes sense. For example, I wouldn’t want to use the Sqair in my kitchen as I would rather not have to drop everything while cooking just to set the dial on three or bring it back down to one. But that could be just me.

However, there is a reason why this unit doesn’t have such features. The team at Smart Air thinks auto-features are a waste of time, as built-in air quality monitors could be inaccurate, and air purifiers might not thoroughly clean the air before the auto-mode switches them back to speed one.

Just high-quality filters and a powerful fan

The Smart Air offers H12 HEPA filtration with an optional activated carbon filter.

This air purifier is one of the simplest units I have come across. As you can see in the video below, it’s simply a large fan combined with a HEPA filter housed in plastic. 

The Smart Air Sqair comes with an H12-type HEPA as standard rather than the trendier medical-grade H13 HEPA. The reason for this is airflow.

H12 allows more air to pass through the filter, meaning that the air purifier can clean more air without working as hard. This not only makes it more efficient at cleaning the air but also reduces the amount of electricity it consumes.

That said, you can choose to get your Sqair with a H13 filter, but you need to be aware that using a stronger grade of HEPA will reduce the airflow.

The Smart Air Sqair comes with a HEPA filter, but you will need to buy the activated carbon filter separately (for an extra $29.99).

Most manufacturers include both HEPA and activated carbon as standard, partly because it makes for a more well-rounded air-cleaning solution and partly because it will keep you buying more filters.

But Smart Air doesn’t include these filters as standard because the truth is that not everyone needs an activated carbon filter, and using one will reduce airflow.

I highly recommend you buy the activated carbon filter only if you want to use your air purifier to remove unwanted smells, gases and VOCs, as HEPA won’t be able to help with that.

Installing the activated carbon filter is super easy. There are no fiddly, twisty mechanics or screws to find the right tool for. You just need to follow three easy steps:

Told you it was easy. Want to get one for your Sqair, too? Here you go:

The Smart Air Sqair cleared our test room in 32 minutes

As with every air purifier we review here at HouseFresh, I tested the Sqair in our 728 cubic ft. test room (a fairly small home office) and used an incense stick to create airborne pollutants. I then used two different Purple Air indoor sensors (Touch and Zen) to track how quickly the Smart Air could reduce PM1 pollutants down to zero while running at its top fan speed.

The Smart Air Sqair removed all PM1 pollutants in 32 minutes.

Air cleaning speed, compared

Let’s put these results into perspective by comparing the Sqair to other units we have tested. So, here’s how it compares to other air purifiers in terms of noise output, air cleaning speed and initial price. 

Noise levels, compared

When you compare noise levels generated by the Sqair to other units, it’s perfectly average. Yes, you’ll hear it when it’s on full power, but it won’t command the whole room.

Now, I always explain that sound can be subjective, so I shot a video so you can listen to the noise levels it generates:

The cost to run a Smart Air Sqair: $114.98 per year

The costs associated with running air purifiers in the long term are usually overlooked, but they are an important factor to consider — especially if you’re planning on actually using your air purifier regularly enough to keep the air in your home clear of pollutants.

1. Electricity costs = $41.00

As part of my testing, I used a power meter to measure how much electricity in watts the Smart Air Sqair pulls at each fan speed.

• Power 1 – 5.6 watts
• Power 2 – 19.7 watts
• Power 3 – 39.4 watts

The team at Smart Air has created something very special with the Sqair, a good-looking air purifier with a decent CADR that also uses less energy than most other similarly sized units. 

The energy savings might be down to the fact that the Smart Air Sqair uses a H12 filter instead of a H13, no-pre filter, and (what I assume to be) a more efficient fan.

2. Filter costs = $73.98

Another long-term cost to consider is filter replacement. With mechanical filter technology like HEPA, the filters get full of pollutants and need to be replaced regularly.

The Sqair has filters available for $36.99, and they suggest replacing them every 6 months. Running a Sqair will cost you $73.98 per year on HEPA filters alone.

Here is how that compares to other units:

When it comes to long-term costs, the Smart Air Sqair is not the cheapest air purifier to run 24/7 but close: the S is the second cheapest option when comparing its running costs to those of units in the same price range or the same size:

Bottom line: Is the Smart Air Sqair worth it?

Smart Air is a brand on a mission and with the Sqair, they’re showing us they mean business. 

By taking a simplistic approach to air purification, they have achieved amazing air cleaning performance without the energy consumption and filter replacement costs you can expect from competitors. 

Its a good device for smaller spaces and benefits from the simple controls and attractive design.

The Smart Air Sqair is not the right air purifier for you if you care about smart features and are looking for an air purifier with a fancy touchscreen or an on-board air quality sensor. If those are the kind of things you want in your device, then you should check out my review of the Levoit Vital 200S.

However, if you are on the market for a good looking device that will blend into the decor of your home and STILL be able to clean the air as efficiently as units priced upwards of $200, then the Sqair might just be the thing. Just remember to buy the additional activated carbon filter if you are wanting to rid your home of unwanted smells and VOCs.