Smart Air Filters

200RMB

The Original

For 228 RMB, we’ll send you our improved fan, a HEPA filter, and a strap. Get this simple yet effective DIY air purifier delivered to your door today, shipping included.

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470RMB

The Cannon

Stronger fan, lower particle counts, and faster clean air. If you’re looking to clean a larger area, check out our powerful Cannon purifier kit. Same HEPA, just pushing more air through it.

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80RMB

HEPA filters

HEPA filters are what trap small particles like PM 2.5, and they’re not expensive! We buy ours straight from the factory so we can pass the savings on to you.

Why use our HEPAs?

0RMB

Knowledge

We think if more people knew how air filters works, they’d think twice about paying thousands of RMB for clean air. Check out Particle Counting, attend a workshop, or:

See the data »


What the press is saying

 

BBC 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.”

See the episode.

Forbes

“Talhelm’s research suggests the 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.”

Read more.

CCTV

“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.”

Read more.

Bloomberg

“Using a HEPA filter strapped to a simple flat-surfaced fan, he found that the device reduced indoor levels of PM 0.5 by 84 percent and indoor levels of PM 2.5 by 92 percent. When he tested a more powerful rotating fan, the results were even better.”

Read more.


Introducing the Smart Air DIY Air Purifier

 

Purification Effectiveness

Average percent reductions of Original DIY Air Purifier, based on 8-hour tests in a 200 sq-ft bedroom.

Air Purification Speed

Based on an 8 hour test in a 15 sq-m bedroom.

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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 the Smart Air DIY air purifier 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 or Youku).

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 filter on the opposite side of the room. Here’s what our filter did in one hour:

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And over the course of eight hours:

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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:

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Conclusion: Yes, the clean air from the DIY filter is cleaning the entire room.

 

 


 

 

3. How well does the Smart Air DIY air purifier perform compared to expensive air purifiers?

 

Thanks to kind souls who donated a BlueAir 203/270E (3,600 RMB), a Philips AC4072 (3,000 RMB), and an IQAir Health Pro (8,000 RMB) 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, Anna ran 11 overnight tests with the BlueAir, 9 tests with the Philips, and 11 tests with the IQAir. 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.

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All of the filters significantly reduced particulates, but the 470 RMB Cannon removed as many particles as the highest-performing big brand. Even the 200 RMB Original was only 6% behind the 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:

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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.

 

 


4. Which purifier is right for me?

The Original

The Cannon

200 RMB

470 RMB

Original Cannon

The Original DIY air purifier is good for cleaning pollution in room sizes up to 15m2. The Cannon is twice as powerful and can clean rooms up to 30m2. See our air pollution test results below:

Purification Speed

(based on a 1-hour test in a 1 m2 bathroom with a source of PM.5 pollution. Get the full story here.)

The Original

The Cannon

Original Cannon

Suitable for normal-sized rooms
(< 15 m2).
Quieter than the Cannon.

Suitable for larger spaces
(at least 30 m2)
and anyone wanting clean air fast.