Every unit runs through the same closed 9 m² room, the same PM2.5 gates, and the same noise and power meters. Then we tell you who should buy it, and who should not.
Smart AirSmart Air Blast
Best for offices, meeting rooms, classrooms, and shared spaces up to about 90 m²
Smart AirSmart Air QT3
Best for desks, travel, and a 1.2 m personal zone
Smart AirSmart Air SA600
Best for living rooms, family bedrooms, and condos up to about 45 m²
Smart AirSmart Air Sqair
Best for bedrooms, home offices, and study rooms up to about 30 m²
Our pick for every kind of space
Find your room below. Each pick comes from the test results further down the page.
Living rooms
Up to 45 m²
Our pick
Smart Air SA6008.4/10
Matched its listed clean-air output in our room, with H13 and carbon on both sides and three speeds under 45 dB.
Offices and classrooms
Up to 90 m²
Bedrooms
Up to 30 m²
Desks and travel
About 1.2 m around you
Our pick
Smart Air QT37.0/10
A ฿1,490 battery purifier that keeps a pocket of clean air at your desk or in the car.
The AirLab leaderboard
Sorted by score. Time to clean is how long the top speed took to bring PM2.5 from 75 down to 15 µg/m³ in our 9 m² room.
Top scores in the Lab
Overall score out of 10, from the full review
- 2nd place:
- Smart Air Sqair7.9/10
- 1st place:
- Smart Air SA6008.4/10
- 3rd place:
- Smart Air Blast7.5/10
- Clean-up
- 24 min
- Noise
- 35.2–56.7 dB
- Per year
- ฿4,277
- Price
- ฿7,990
- Clean-up
- 33.5 min
- Noise
- 37.1–54.8 dB
- Per year
- ฿2,363
- Price
- ฿3,990
- Clean-up
- 12.4 min
- Noise
- 41.7–54.3 dB
- Per year
- ฿4,219
- Price
- ฿19,990
- Clean-up
- 291.4 min
- Noise
- 35.8–40.6 dB
- Per year
- ฿1,666
- Price
- ฿1,490
| Purifier | Score | Time to clean (top speed) | Noise (speed 1 to top) | Yearly cost | Price |
|---|---|---|---|---|---|
| Smart Air SA600Rooms up to 45 m² | 8.4 | 24 min | 35.2–56.7 dBQuietest | ฿4,277 | ฿7,990 |
| Smart Air SqairRooms up to 30 m² | 7.9 | 33.5 min | 37.1–54.8 dB | ฿2,363 | ฿3,990 |
| Smart Air BlastRooms up to 90 m² | 7.5 | 12.4 minFastest | 41.7–54.3 dB | ฿4,219 | ฿19,990 |
| Smart Air QT3Rooms up to 4 m² | 7.0 | 291.4 min | 35.8–40.6 dB | ฿1,666Lowest | ฿1,490 |
Noise runs from the lowest to the highest fan speed. Yearly cost is filters plus electricity at ฿4.5/kWh, at the speed and hours used in each review. The QT3 is a desk purifier, so the full room is a stress test for it. Updated .
Inside our test room
Every purifier on this site went through the same closed 9 m² room with a 2.5 m ceiling. This is what that looks like.
01Same start level
Incense sticks bring PM2.5 to 75 µg/m³, then come out of the room before the fan goes on.
02Timing the clean-up
We start a timer when the fan goes on and stop it once a monitor 1 m away shows the air is clean.
03Noise at every speed
Measured 1 m away in a room quieter than 30 dB.
04Watts at the wall
A plug meter gives real power draw, priced at ฿4.5 per kWh.
Tips and explainers
Short guides to the specs that decide whether a purifier is right for your room.
How to use
Where to put an air purifier: placement rules that actually matter
The best spot for an air purifier in a bedroom, living room or office: how much space to leave, how close to the bed, whether to close the door, and the placement mistakes that waste clean air.
Running costs
How much does it cost to run an air purifier?
Work out what an air purifier really costs per year in Thailand: electricity at your fan speed, replacement filters, and the three-year total. Includes simple formulas and worked examples.
Filters
HEPA, True HEPA, H13: what air purifier filter labels really mean
What HEPA, True HEPA, H11, H12, H13 and H14 mean on an air purifier box, how much each grade actually captures, and why filter grade matters less than CADR and a good seal.
Buying guide
What is CADR? The air purifier number that actually matters
CADR (Clean Air Delivery Rate) tells you how much filtered air a purifier delivers per hour. Learn how it is measured, how to size a purifier to your room, and where the number falls short.
Who tests the purifiers
Theeraphat ChonsiriLab Editor
I write every verdict for someone who is about to buy, including when a different kind of purifier is the better spend.
Our scores and verdicts are never influenced by money or affiliate links. Every review says plainly who should skip the product, not just who should buy it. We don't copy numbers from the box: every figure we publish comes from our own measurements.