DIY Purifiers
We’ll send you a fan, HEPA filter, and a strap to your door in Bangladesh for as little as ৳3,200. Get these simple yet effective DIY air filters and clean air in your lungs today.
The Blasts
Stronger fans, bigger air filters, lower particle counts, and faster clean air. If you’re looking to clean a larger area, check out the powerful yet quiet Blast air filters.
HEPA filters
HEPA filters are what trap small particles like PM 2.5, and they’re not expensive! We’ve tested hundreds of different types, and get ours straight from the factory so we can pass the savings on to you.
Knowledge
We think if more people knew about air pollution in Bangladesh, and how air purifiers work, they’d think twice about paying big bucks for clean air. Check out the Smart Air blog, attend a Smart Air workshop, or:
Smart Air in the news

“A group of American expats in Beijing have come up with a novel solution for making indoor air purifiers affordable to everyone. The budget innovation has caught the imagination among residents who battle high levels of air pollution every day.”

“Talhelm’s research suggests the air filter starts to lose its efficiency after three months. But, at about $15 a HEPA, that’s a lot of savings over big international brands like Philips with comparable results.”

“They’re very creative. They have found an easy way that people can accept. I think the price is the key point. It’s so cheap. It attracts normal people like me to come and listen, and then buy it.”
Introducing the Smart Air DIY Air Purifier
Air Purification Speed
Based on an 8 hour test in a 160 sq-ft bedroom.
Does the Smart Air DIY Purifier work?
Short answer: Yes!
Long answer: Keep reading
Let’s break down this question into three smaller questions:
1. Is the air coming out of Smart Air DIY air purifiers clean?
This is the easiest question to answer, and we do it by holding a Dylos DC1100 Pro particle counter in front of the purifier and watching the numbers drop. Here’s a video of Thomas doing just that:
(Can’t see the video? Watch it on YouTube)
Conclusion: Yes, air coming out of the purifier is clean.
2. Is the Smart Air DIY air purifier able to actually clean the air in the entire room?
Answering this question is more difficult because you need a controlled environment (for example, you don’t want to walk in and out of the room during the test), and you need to test the air for a longer period of time. But fortunately for you, Thomas is a huge nerd and does this kind of thing for fun.
To answer this, Thomas set up the particle counter on one side of his 13.5 m2 bedroom and put the DIY air filter on the opposite side of the room. Here’s what our air filter did in one hour:
And over the course of eight hours:
The particle counter also gives data on .5 micron particles — even smaller than the 2.5 micron reading. Here’s what that looks like over eight hours:
Conclusion: Yes, the clean air from the DIY air filter is cleaning the entire room.
3. How well does the Smart Air DIY air purifier perform compared to expensive air filters?
Thanks to kind souls who donated a BlueAir 203 (৳24,990 taka), a Philips AC4072 (৳21,195 taka), and an IQAir Health Pro (US$ 849) we’ve finally been able to test the DIY against expensive brands in the same room, for the same amount of time, with the same particle counter.
To do that, our colleague Anna from Smart Air China ran 11 overnight tests with the BlueAir, 9 tests with the Philips, and 11 tests with the IQAir. Smart Air founder Thomas calculated effectiveness as percent reduction in particulates from the room air. Anna tested the air before she turned on the air filter, and then set the particle counter to take hourly measurements of the air in her 15 m2 Beijing bedroom. Anna used the highest setting on each filter.
All of the air filters significantly reduced particulates, but the Cannon (now succeeded by the Sqair) removed as many particles as the highest-performing big brand. Even our ৳3,200 taka DIY 1.1 air purifier was only 4% behind the ৳24,990 taka Blue Air on the .5 micron particles and 4% behind on the 2.5 micron particles.
Among the different brands, there seems to be no relationship between price and particulate removal:
Conclusion: You can remove particulate pollution from the air in your home and pay far less than the cost of a Blue Air, Philips, or IQAir air purifier.
4. Which purifier is right for me?
DIY 1.1 |
The Sqair |
৳3,200(plus shipping) |
৳10,500(plus shipping) |
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The Sqair produces more clean airThe Sqair is the most cost-effective purifier in the world. Get the full story here. |
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