Air scrubber

I've been wondering what I might do to control air quality in my very small shed. It's 1.5x1.8x2.1M, or 5.7 cubic meters, or 200 cubic feet.

If I was just going to buy something specifically for this purpose, this WEN air filtration system costs £112, and would suck all the air in my shed through it twice in a minute. It's not massive - 50x45x25cm, but it would help if it was smaller, and it's noise isolation requires it to be hung from the ceiling, which I can't do if I don't want to bang my head on it.

Lots of people have posted on YouTube on how to make air filtration systems using box fans. They are generally scaled up compared to the WEN, rather than down.

This video points out why using a box fan isn't that good an idea. It's a rather over-complicated solution though: you can just buy a plate fan that includes a baffle. I suppose it's great if you have a fan you don't want.

This video is the only attempt to make something significantly smaller, for a smaller space, but it ends in failure. Note that I can easily buy an extractor fan that moves 10x as much air as a cheap bathroom extractor, and more than the WEN, for that matter. Having a washable filter seems attractive, but it's only the Dyson pre-motor filter that's washable. The HEPA filter isn't. The Dyson filters may require too much static pressure. As it happens though, I have a set of filters from a DC05, so I could try it without any expense.

It seems unlikely the Dyson filters will be a good match for this application. It's more likely the filters from a high throughput de-humidifier

How am I going to test the effectiveness of what I make? Last time I looked at this, it was expensive to do properly, and I bought some cheap GP2Y1010AU0F sensors, which I couldn't get to work. This time, I've found the PMS5003, which comes complete in a box with a fan for about £15. Of course it's not calibrated, and I have to attach it to a micro controller, but I can easily add data logging this way. I just need to wait for it to arrive...

This article provides lots of useful information about the GP2Y1010AU0F. I could certainly use one of these for a comparison with or without the filter.

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