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Build a do-it-yourself home air purifier for about $25

uofmhealth.org

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Re: Build a do-it-yourself home air purifier for about $25

#341

Post by marco1 »

benbojangles wrote: post #85

I built my own air purifier in 2016, living in London, I was living in a basement and was having breathing problems due to mould. My landlady was gaslighting me at the time, so I built the air purifier. It worked for a while but mould spores cling to the paper filter and eventually grow into the filter material. I think Dyson uses glass fiber filter to stop this problem. My filter helped a lot, but eventually I had s…

Really sorry to hear that.

Sorry to ask, but I’m not really sure I got it right: Do you think the DIY air purifier was the cause of these health problems? Or did it at least contribute by letting the mold come back (inside)?

As others have noted, a dehumidifier could help. But what prevents mold from growing inside these dehumidifiers as well? Sure, they’re mainly built from plastic and metal, so no paper as in your case. Will that be enough to prevent mold (or bacteria)?

Otherwise, a dehumidifier could turn into yet another health hazard over time.

Re: Build a do-it-yourself home air purifier for about $25

#342

Post by marco1 »

electic wrote: post #110
benbojangles wrote: post #85

I built my own air purifier in 2016, living in London, I was living in a basement and was having breathing problems due to mould. My landlady was gaslighting me at the time, so I built the air purifier. It worked for a while but mould spores cling to the paper filter and eventually grow into the filter material. I think Dyson uses glass fiber filter to stop this problem. My filter helped a lot, but eventually I had s…

Woah, this is pretty scary. Thank you for sharing. How did you know it was mold that was in the air? Is there some sort of test kit that you can buy to test for this. Mold is pretty hard to detect because you can't really see it because it typically hides between the walls. Any advice appreciated.

You can buy test kits that you expose to your rooms’ air for some time, and then a lab will grow the mold inside the Petri dishes to “amplify” what has been collected in your home. That may be expensive, though, and not easily available everywhere, and perhaps even prone to contamination “in transit”?

Re: Build a do-it-yourself home air purifier for about $25

#343

Post by marco1 »

the_clarence wrote: post #124
electic wrote: post #110

Earlier quoted context omitted.

Woah, this is pretty scary. Thank you for sharing. How did you know it was mold that was in the air? Is there some sort of test kit that you can buy to test for this. Mold is pretty hard to detect because you can't really see it because it typically hides between the walls. Any advice appreciated.

You can notice black spots in your bathroom or other places where steam doesn't escape properly. I noticed it on my mattress also. I don't think I have any health issues because of that, it was 5 years ago, but it was rough.

Mold is not always black, is it? It can have other colors as well, e.g. yellow.

Re: Build a do-it-yourself home air purifier for about $25

#344

Post by sylvainkalache »

chaostheory wrote: post #226
abalone wrote: post #82

Can we talk about Molekule? Their team and some SF tech community folks have been plugging it all over Twitter during this tragic wildfire crisis. But it seems like snake oil to me. It’s $800. Certainly for smoke particles it can’t possibly offer any more protection than a standard HEPA filter. But even for its claimed ability to nuke VOCs, the claim seems ridiculous. While particles can deterioriate under prolonged…

I had one. It has multiple issues: 1. CADR is really low to the point where the unit is near useless due to #2 2. In addition to a low CADR, it has the highest noise. It looks and sounds like a jet engine when you have this thing on high, which is needed due to the low CADR. This is the loudest air purifier that I’ve ever owned 3. If you get a defective main filter, the unit will emit an unpleasant metallic smell. I…

What other smart air cleaners do you recommend?

Re: Build a do-it-yourself home air purifier for about $25

#347

Post by JesmineTyler »

"Apparently, the contractor let the drywall get soaked while sitting on palettes during monsoon season, and since the roofing wasn't done there were inches of standing water that resulted in black mold.

They just drywalled right over it. In the US. In 2018. In a luxury condo." I am sure such things happen everywhere in the world. I have lived in China for a long time, and you won't ever know how worse some of the construction companies are, they just want money by keeping things just looking good in the appearance.

Re: Build a do-it-yourself home air purifier for about $25

#348

Post by fludlight »

rsync wrote: post #297
clumsysmurf wrote: post #162

Earlier quoted context omitted.

I was talking to a buddy that does construction work in a pretty wealthy area (Scottsdale, AZ). They are just finishing up a large luxury apartment. Apparently, the contractor let the drywall get soaked while sitting on palettes during monsoon season, and since the roofing wasn't done there were inches of standing water that resulted in black mold. They just drywalled right over it. In the US. In 2018. In a luxury co…

"They just drywalled right over it. In the US. In 2018. In a luxury condo." This happens regularly in the SFBA, in Marin County. Every rainy season I see at least one house being built through Nov-Dec-Jan that is in the bare studs stage and gets soaked with a week or so of constant rain. And then the sun comes out and they immediately tyvek wrap and seal the whole house up. Sopping wet, soaked studs, entrapped on bot…

This exact scenario is going to play out near my house over the next two weeks. SF Bay $2m houses. I should send pictures to the county building inspector.

Re: Build a do-it-yourself home air purifier for about $25

#349

Post by erikpukinskis »

rsync wrote: post #297
clumsysmurf wrote: post #162

Earlier quoted context omitted.

I was talking to a buddy that does construction work in a pretty wealthy area (Scottsdale, AZ). They are just finishing up a large luxury apartment. Apparently, the contractor let the drywall get soaked while sitting on palettes during monsoon season, and since the roofing wasn't done there were inches of standing water that resulted in black mold. They just drywalled right over it. In the US. In 2018. In a luxury co…

"They just drywalled right over it. In the US. In 2018. In a luxury condo." This happens regularly in the SFBA, in Marin County. Every rainy season I see at least one house being built through Nov-Dec-Jan that is in the bare studs stage and gets soaked with a week or so of constant rain. And then the sun comes out and they immediately tyvek wrap and seal the whole house up. Sopping wet, soaked studs, entrapped on bot…

I'm designing a home fabrication system, so this stuff is very fresh on my mind right now.

This talk really gave me a foundation for understanding how moisture works in a building enclosure through seasons: https://www.youtube.com/watch?v=Ld8pzIu45F8

The speaker is a little hammy, but he's doing (more or less) legitimate science, and he laid out a bunch of principles I didn't understand before.

In particular, the different layers of the wall (ballistic, water, insulation, vapor, structure) really need to go in the right order, and at literally every exterior joint in the house you need to match up all five layers. There are also several layers that it is crucial to vent/drain.

It's extremely complicated, and for the most part just obeying code and convention will only get you 80% of the way there.

It seems to me there are also anti-patterns ensconced in code and convention. The idea that insulation goes inside the structural layer for example. You want your insulation layer to be unbroken.

Re: Build a do-it-yourself home air purifier for about $25

#350

Post by leetbulb »

mattlondon wrote: post #263
leetbulb wrote: post #27

Earlier quoted context omitted.

Screw Dyson. Get a Winix HR1000. You can find them cheap ($200 or so) on eBay every so often. I picked up two a couple years ago and am very happy with them. You only need to replace the filters once a year. They've made a HUGE difference with my allergies. They automatically adjust airflow based on built-in air quality sensors. They are completely silent, aside from the "turbo" mode (~300CFM lol), but if you like wh…

We recently got a Winix U300 (1) for about £150 new. It is basically a HEPA + Activated Charcoal filter and it claims it has some "plasmawave" thing that generates "free radicals" that kills odors and viruses. Initial searching suggests that this might be true, but I am unsure if there is any way to really test it. The air quality sensor certainloy works if you drink a strong coffee then go and blow into the sensor -…

Sounds like a fun project with the ESP! I personally don't care for the WiFi stuff, although the app's air quality graph is pretty neat.

I have no way to really measure its effectiveness, but it very quickly removes any cooking smells and has fixed my year-round allergies while indoors.

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