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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

#201

Post by adrianN »

fyfy18 wrote: post #157
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.

The CDC has some recommendations on it (yes you can have mold tested to see if it's dangerous): https://www.cdc.gov/mold/stachy.htm I'm not really sure about keeping the humidity below 50% though. The UK and most of Northern Europe has rather high humidity in the winter. It commonly reaches 80-90 RH outside, so you'd have to heat your house to 25c/77F to bring the humidity below 50%.

Heating your home to like 25 degrees and opening the windows every six hours is actually required in some tenancy agreements.

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

#202

Post by z3t4 »

peferron wrote: post #177
ramenmeal wrote: post #168

Earlier quoted context omitted.

Could you explain? I'm curious why it'd be better to have the air filter going rather than having good airflow from outside via open doors and windows? Are we trying to filter dust/ things produced in the house, or pollutants from things outside the house?

Yeah, sorry, just assumed that pollutants were coming from outside. I'm just so used to it after living several years in China and now being affected by California wildfires. If the outside air is better than inside, then yeah you probably should air out your home as much as possible unless it's unbearably hot or cold outside :)

You could also put the filter on the air intake.

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

#203

Post by Cthulhu_ »

a012 wrote: post #180
adinobro wrote: post #155

Earlier quoted context omitted.

I know there is mould in my house. We do three things to deal with it: 1. Air Filter (more for pollution but it helps with mould) 2. Dehumidifier which we leave on 24/7 basically for the mould. This is the big one. 3. Wash any mould with vinegar to change the PH after it is wiped off to prevent it from growing back. The mould is still there but the dry air stops it from growing and sporing which is what makes you sti…

Dehumidifiers are expensive in power consumption, I don't know which model is more effectively. I'm living in SEA, and get humidity level to 50% 24/7 in my studio equally to double my monthly electricity bill.

I don't know if these are effective, but in my country we have passive dehumidifiers which are basically containers with a load of salt or something like that which draws the moisture out of the air. Good enough to keep caravans in storage mold free. Probably not good enough for e.g. living rooms or actually moist locations, but maybe it scales up. Of course, you'd then need a lot of salt or whatever the stuff is.

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

#204

Post by Tharkun »

adrianN wrote: post #201
fyfy18 wrote: post #157

Earlier quoted context omitted.

The CDC has some recommendations on it (yes you can have mold tested to see if it's dangerous): https://www.cdc.gov/mold/stachy.htm I'm not really sure about keeping the humidity below 50% though. The UK and most of Northern Europe has rather high humidity in the winter. It commonly reaches 80-90 RH outside, so you'd have to heat your house to 25c/77F to bring the humidity below 50%.

Heating your home to like 25 degrees and opening the windows every six hours is actually required in some tenancy agreements.

What? That's an insanely uncomfortable indoor temperature. Anything over 20 and I'm uncomfortable.

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

#205

Post by sdwisely »

ed_balls wrote: post #52

I wonder if you'd put cotton wool, how effective it would be. Here is my set up: - I bought XIAOMI Mi Air Purifier 2 straight from China for $137.00 and spent 1 euro on a EU plug. It's so quiet that I can sleep next to it, looks nice and it's quite compact, so doesn't take up much space. It has a particle detector to adjust the fan speed. The app is useless, so a cheaper version without WiFi and bluetooth would be gr…

> The app is useless, so a cheaper version without WiFi and bluetooth would be great.

have you tried it with hass (home assistant)? I've been considering getting one and running it via that instead.

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

#206

Post by jlangenauer »

Scoundreller wrote: post #114
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…

> I was subletting so had no grounds for complaint How does that work? You may not be eligible for regular tenant protections, but you're still eligible for recourse through regular courts, no?

This is in the UK. Laws protecting tenants there are, to put it politely, pretty thin.

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

#207

Post by JofArnold »

evolve2k wrote: post #76
ed_balls wrote: post #74

Earlier quoted context omitted.

> health impact of its cheap plastics Do you mean the health impact of when the device is thrown away?

I think they mean of small plastic particles coming off the cheap device and polluting the air.

More likely they mean volatile organic compounds (VOCs)

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

#208

Post by Foobar8568 »

Tharkun wrote: post #204
adrianN wrote: post #201

Earlier quoted context omitted.

Heating your home to like 25 degrees and opening the windows every six hours is actually required in some tenancy agreements.

What? That's an insanely uncomfortable indoor temperature. Anything over 20 and I'm uncomfortable.

In Switzerland, they have a tendancy to overheat, now I am used to a constant 25°C over the year. It's actually quiet comfortable.

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

#209

Post by thewhitetulip »

TeMPOraL wrote: post #187
thewhitetulip wrote: post #165

Earlier quoted context omitted.

What? I have read the report myself. They put in Benzene inside a sealed room and one of these plants. A few hours later the Benzene was gone! Absorbed by the plant. They did the same with formaldehyde too and other harmful substances. Isn't that the bar for purification? This is still better than mere air dolter that are costly and requore frequent maintenance

I think the key term here is sealed room . And this does not invalidate the study, only helps evaluate the results in context of applying at home or office. I.e. it's still gonna help, but unless you restrict your airflow, not as much as you'd like. Though the same caveat probably applies to all air purifiers too.

>Though the same caveat probably applies to all air purifiers too.

So whatever reservations you have against plants as air purifiers apply verbatim to commercial air purifiers. Then why the bias against plants?

Funny how you contradicted yourself, not to mention those downvoting me for speaking about plants and yet being enthusiastic about air filters!!

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

#210

Post by adrianN »

Tharkun wrote: post #204
adrianN wrote: post #201

Earlier quoted context omitted.

Heating your home to like 25 degrees and opening the windows every six hours is actually required in some tenancy agreements.

What? That's an insanely uncomfortable indoor temperature. Anything over 20 and I'm uncomfortable.

I believe the idea is that the landlord is never responsible for mold problems since no sane tenant could comply with those rules.
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