One particular popular air purifier in Thailand and the Philippines, which goes by many names, has become a bestseller in recent years. The air purifier, often called an “OEM”, promises an effective air purifier at a price far lower than the competition. But is the “OEM” air purifier actually effective? To find out, we tested and reviewed this popular Philippines and Thailand air purifier.
NOTE: OEM air purifiers are imported from China and local vendors simply put their own logo on it and sell it in their local market. Therefore, there are MANY brands that sell the same-looking air purifier that we review below. Some brands in the Philippines include “Kaisa Villa air purifier” and “SHANEN smart air purifier”.
Thailand and Philippines Bestselling Air Purifier “Too Good to Be True”?
This air purifier claims CADR (Clean Air Delivery Rate) of 230 m³/hr which would be strong enough to provide clean air for rooms up to 30 sqm. Sellers even advertise it to be able to clean up to 50 sqm.

The combination of a 230 m³/hr CADR and an incredibly low price has made the purifier a bestselling air purifier in Thailand and the Philippines. Bargain hunters could even buy it for 590 Baht (17 USD) during the low season. 100,000+ of these air purifiers have been sold in Thailand.
We at Smart Air have never made a secret of the simple science behind air purifiers. Air purifiers, in fact, are just fans and HEPA filters. Both components are cheap and easy to source.
We sold our very first air purifier for just under $30 as well and it worked great. However, this cheap air purifier in Thailand seemed to be too good to be true. So we decided to test and review the air purifier.
The Test: How Strong is This “OEM” Air Purifier?
To test out the OEM air purifier claim of a 230 m³/hr CADR, I converted my 20 sqm guest room into a test station. I switched my Laser Egg air pollution monitor on and lit up an incense stick. Once PM2.5 spiked up AQI 240, I turned the air purifier on high. According to the manufacturer, this air purifier can clean 230 cubic meters per hour. My room has 50 cubic meters. Theoretically, the air should be clean after 10-15 minutes.

Results: The Purifier Can’t Cover More than 10 Square Meters
In truth, it took a lot longer than 10 minutes to clean the room. After 10 minutes, AQI dropped from 240 to 190. After another 20 minutes, AQI only went down to 150 which is still very unhealthy. Long story short: this air purifier needed 54 minutes to bring air quality below 50 AQI. Considering the data, it is highly unlikely this air purifier has a CADR of 230 m³/hr. A value between 60 and 70 m³/hr is much more realistic which means that this air purifier can’t cover spaces bigger than 5-10 square meters.

For comparison, I tested the cleaning speed of the Sqair air purifier under the same conditions. The Sqair has a certified CADR from independent labs of 315 m³/hr. It only took 16 minutes to bring AQI values of above 200 down to below 50. Below is a comparison of the two air purifiers’ performance.
Update: Official Report Shows True CADR
After the at-home tests, we at Smart Air decided to send the air purifier to an official CADR lab to verify our results. The results were similar to what we expected, with an official CADR of just 75 m3/hr, less than 1/3 the marketed CADR.
Open Data: Thailand OEM Air Purifier CADR Tests
Other Concerns of the Bestselling Thailand Air Purifier
The poor performance of the bestselling Thai air purifier was not the only area of concern.
Questionable Built-in Air Quality Sensor
After burning down a complete incense stick, the reliable Kaiterra Laser Egg air quality monitor displayed 192 ug/m³ of air pollution which equals an AQI value of 242. The no-brand air purifier, however, showed a PM2.5 level of only 23 ug/m³ equivalent to an AQI of 73. Conclusion: The built-in PM2.5 reader is completely useless. We have found other air purifiers such as the Xiaomi air purifier to have inaccurate, useless air quality sensors.

Dangerous Ionizer Technology
Equally questionable are all the other functions that seem to be part of this air purifier. Ionizers are proven to cause more harm than good thus they’re not needed. Furthermore, reliable TVOC sensors are usually priced at a couple of hundred dollars; the one in this machine costs not more than a few Thai Baht. Quite mysterious is the so-called disinfection function. At no point could I spot a UV light on this air purifier that could* kill viruses. What the disinfection function is all about remains a secret.
How to Find Reliable Air Purifiers
As we have shown, you can not directly trust the information some air purifier companies give you. Ideally, you would verify the effectiveness of an air purifier in the following two ways:
- Request 3rd party test results
To make sure whether an air purifier has reliable performance, ask for 3rd party test results that verify the advertised CADR value of an air purifier. If sellers don’t provide any certifications, better stay cautious.
- Get an external air quality monitor
Since built-in air quality monitors are typically not reliable, an external PM2.5 reader that you can place a couple of meters away from the air purifier is helpful to monitor the cleaning performance of your air purifier.
Read More: Here Are the Most Accurate PM2.5 Air Quality Monitors
Bottom Line: Be Aware of Fake CADR Claims
This reviewed air purifier likely has a CADR rating far less than the manufacturer claims. 5-10 square meters. Do not trust an air purifier’s claimed CADR, ask for CADR certificates.
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