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Smart Air

smartairfilters.com

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Re: Smart Air

#81

Post by xarien »

acgourley wrote: post #24
simonsarris wrote: post #13

This is a very neat idea, though I suspect they'll ultimately want a more powerful fan. Note that high quality air filters also have a carbon pre-filter that gets changed more often than the HEPA filter, and having one ought to make your HEPA filter last much longer, especially in somewhere like Bejing. They also play a part in controlling odors. This is what I'm currently using and love it to death. Note that the cu…

I'm still trying to reconcile the $300 price tag of yours with the price tag of a carbon filter (5 on amazon) HEPA filter (70 on amazon) and box fan (30 on amazon). Is there really 200 dollars worth of plastic, assembly, marketing and IP in the the whispure? Or is there one important element I'm not accounting for (perhaps fan power, fan noise, some kind of PID, or sensors to check filter health)

The site states RMB which stands for Ren Ming Bi, aka Yuan, aka PRC currency. It looks like a very specific market and I can see what they put together a DIY kit to drive the cost down given the market.

Re: Smart Air

#82

Post by Havoc »

jmpe wrote: post #12
ksec wrote: post #9

I am actually looking for a solution where the filtering is done through water rather then a HEPA filter, which needs replacing quite a lot in a environment as bad as Bejing.

Use aquarium air stones. The smaller the bubbles and higher the column of water the better.

Those require reasonably high pressure and push low volumes though?

Re: Smart Air

#83

Post by Havoc »

chopin wrote: post #68

Axial fans, especially those for household purposes do not offer the required pressure drop of approx. 300 Pa ( https://en.wikipedia.org/wiki/HEPA#Specifications ). Axial fans have typically a high throughput but low max pressure difference (see eg. http://www.adrianagarcia.me/wp-content/themes/twentyeleven/a... ). HEPA filters require radial (or centrifugal) fans for acceptable throughput. As well, a HEPA filter bec…

>Axial fans, especially those for household purposes do not offer the required pressure drop of approx. 300 Pa

It might fall short of the official specs, but its difficult to argue with their results.

What kind of prefilter would one need? I'm thinking of DIYing this...

Re: Smart Air

#84

Post by Goopplesoft »

eru wrote: post #76
Goopplesoft wrote: post #61

Earlier quoted context omitted.

Ah the perils of text language. You're not sure if he's referring to both bacteria and pet dander or just pet dander.

Yes, it's somewhat ambiguous. You don't even know if they kill bacteria and they pet [verb] dander. English grammar is crazy ambiguous.

hah good catch, pretty crazy actually.

Re: Smart Air

#85

Post by chopin »

Havoc wrote: post #83
chopin wrote: post #68

Axial fans, especially those for household purposes do not offer the required pressure drop of approx. 300 Pa ( https://en.wikipedia.org/wiki/HEPA#Specifications ). Axial fans have typically a high throughput but low max pressure difference (see eg. http://www.adrianagarcia.me/wp-content/themes/twentyeleven/a... ). HEPA filters require radial (or centrifugal) fans for acceptable throughput. As well, a HEPA filter bec…

>Axial fans, especially those for household purposes do not offer the required pressure drop of approx. 300 Pa It might fall short of the official specs, but its difficult to argue with their results. What kind of prefilter would one need? I'm thinking of DIYing this...

>It might fall short of the official specs, but its difficult to argue with their results.

For this one would need to know the exact measurement setup. For real world performance it is important to know the approximate exchange rate of air of the room. The throughput of the fan across the filter must be considerably higher than that.

>What kind of prefilter would one need? I'm thinking of DIYing this...

First of all, you would need a radial fan to overcome the required pressure drop. As for the prefilter, I am from Europe, which has probably different standards than the US, but some overview is provided here: http://www.filtration-engineering.co.uk/air_filter_testing.h... . For my clean room set up I had a EU5 prefilter combined with a EU9 main filter. Afair, laminar flow boxes for dirty environment (i.e. not supposed to be used within a clean room) have EU5 (or the equivalent) prefilters as well.

Re: Smart Air

#86

Post by dopkew »

talhelmt wrote: post #56
pervycreeper wrote: post #20

Are particles the whole story when it comes to air pollution, or do you have to worry about gases, too? Also, what would be a good source for obtaining HEPA or carbon filters in Canada/USA?

Hey, this is Thomas, founder of Smart Air. Excellent question! Particulates are very important, but gases can be a problem too. We talk about gas pollution in our workshops, and I've written about it on Particle Counting: http://particlecounting.tumblr.com/post/60881490803/the-limi... However, I don't know of home filters that target gases.

There are various indoor plants that are said to help with indoor pollution.

Re: Smart Air

#87

Post by jmpe »

Havoc wrote: post #82
jmpe wrote: post #12

Earlier quoted context omitted.

Use aquarium air stones. The smaller the bubbles and higher the column of water the better.

Those require reasonably high pressure and push low volumes though?

A cheap air pump for an aquarium will produce enough pressure for a string of air stones. I have a 10$ pump (2W) on my desk here that blows 4 stones and I still have to limit the flow a bit or the display looks more violent than soothing. More expensive pumps not only have more power but will also have a better design with less noise.

Re: Smart Air

#88

Post by Havoc »

chopin wrote: post #85
Havoc wrote: post #83

Earlier quoted context omitted.

>Axial fans, especially those for household purposes do not offer the required pressure drop of approx. 300 Pa It might fall short of the official specs, but its difficult to argue with their results. What kind of prefilter would one need? I'm thinking of DIYing this...

>It might fall short of the official specs, but its difficult to argue with their results. For this one would need to know the exact measurement setup. For real world performance it is important to know the approximate exchange rate of air of the room. The throughput of the fan across the filter must be considerably higher than that. >What kind of prefilter would one need? I'm thinking of DIYing this... First of all,…

Interesting. Why do you have a clean room if I may ask? I'm guessing data recovery?

Re: Smart Air

#90

Post by chopin »

Havoc wrote: post #88
chopin wrote: post #85

Earlier quoted context omitted.

>It might fall short of the official specs, but its difficult to argue with their results. For this one would need to know the exact measurement setup. For real world performance it is important to know the approximate exchange rate of air of the room. The throughput of the fan across the filter must be considerably higher than that. >What kind of prefilter would one need? I'm thinking of DIYing this... First of all,…

Interesting. Why do you have a clean room if I may ask? I'm guessing data recovery?

I was in making photographic (those with silver halide) plates in the 90's. That's a wet chemistry process which does not tolerate any dirt in the final product. I made a good deal of the required machinery on my own so I have some basic knowledge on clean room design (albeit a bit rusty).
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