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0.3um is too big, the particles referred to in the article are <0.1um.



You're right! The article concerns Ultra-Fine Particles.

https://en.wikipedia.org/wiki/Ultrafine_particle

A HEPA filter will still do some good, though, and 0.3um is about as small as can reasonably be found on consumer-level filters.

See http://sentryair.com/blog/tag/hepa-for-ufp/

Edit: From the article:

  As you can see in the photos the 3D printer produced over 
  190,000 particles of varying sizes.

  After the Model 300 pulled the particle-laden air through 
  its HEPA filter, the scanner detected 0 particles at the 
  unit’s air output.


IQAir HealthPro Plus claims 0.003 and honestly, I believe it. Disclaimer: I work for them but my opinions are my own and backed by some really great science/technology.


Cool! $1000 for a "Hyper HEPA" filter.

Maybe a good insurance investment for the company with a room full of 3D printers... after they pay for the HVAC guy to come in and install some real exhaust ventilation duct work.


Just want to point out that any company can use the word "HEPA" as there is really no industry standard/federal minimum for what it means to be HEPA. So you can basically have a paper towel in the back of a fan and call it a HEPA filter.


Can you expand on this? It does look like there are HEPA specifications[0]. Are you saying that a product that doesn't meet those standards can still legally be labeled as HEPA? Yikes!

[0] E.G., http://energy.gov/sites/prod/files/2013/06/f1/doe-std-3020-2... and https://en.wikipedia.org/wiki/HEPA#Specifications


Hi! Sorry for the late response.

You are mostly correct. However, per your links, using "HEPA" with any prefix or suffix is problematically allowed. The specifications laid out by the DOE are mostly for DOE facilities and so they have their own version. Everyone else is using their own brand of "-HEPA-" which can mean <0.003 pm or not and is therefore misleading.


Thanks for the response! To make sure I understand this correctly: If I find a product labeled as "HEPA" (w/o a prefix or suffix such as "type," "like", "style," and "99%") then I can be assured that the product does meet the standard of removing 99.97% of particles that have a size of 0.3 µm?


I'm considering to buy an IQAir and I also buy their arguments.

But I was surprised when I saw The Wirecutter review:

http://thesweethome.com/reviews/best-air-purifier/

Korean machines seemed to perform as well as IQAir and BlueAir, and they are quite cheaper (and use more efficient engines). Any comments?


I've owned a bunch of air filters but I like the IQAir ones the best. IQAir machines are built around a very heavy-duty prefilter that traps all the hair, dust, and large particles (maybe pollen-size?). The HEPA filter thus only gets a stream of tiny particles, so it lasts quite a while. Other models I've used (Plasmacluster, Rabbitair) do fine with brand-new filters but quickly accumulate dust that you have to vacuum out, and even then, the HEPA filter is probably already ruined. They also aren't sealed as well, so you don't get to hold up your particle counter to the exhaust and see a nice "0". (But the particle count in the room does decrease versus not running them, so they do do something.)

The IQAir machines don't need any maintenance other than buying new filters when it tells you to. If you are trying to save money, don't buy IQAir.

I try to evaluate effectiveness qualitatively and quantitatively. When I first got an air filter for my bedroom, I noticed that suddenly I didn't feel like coughing all night long. When I got the IQAir for my bedroom, I woke up the next morning with a sore throat because the back of my throat was totally dry. My chronic post-nasal drip was gone. It could have been my imagination, so I bought a laser particle counter to measure the particle count in my room. It was 0. (And it's counting the sub-micron particles.)

(There are some caveats. Moving around in bed is particle city, so you're not breathing 100%-fresh air all night. But the filters take care of things very quickly, and I run them on a high setting, and they're close to my bed. You'll need earplugs. Air filters on the "silent" setting do approximately nothing. This was not a problem for me because I've slept with earplugs for years due to annoying cats. Now I can't sleep without them, the sound of sheets moving against each other is annoying :)


Really glad you like our product. I will admit it is pretty expensive, but as you've said, your particle count will get to almost 98% of less than what was originally lurking in your rooms. That is nowhere near what other air purifiers can do.

When I first joined the company, I was told not to put it on full blast the first night otherwise your mouth will become dry. It still blows my mind that people experience that.

I keep mine on throughout the night as well, but I have definitely noticed the sound doesn't have the humming sound as opposed to other air purifiers. It is a much quieter, fan like sound.


Yeah, it's definitely not as annoying as other models I've tried. The RabbitAir one has a really annoying high-frequency component that prevents me from running it on its highest setting even with earplugs.

Now I just need to buy a house so I can get a Perfect 16 installation and move the noisemaking equipment out of my bedroom.




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