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The Weight of Numbers: Air Pollution and PM2.5

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Re: The Weight of Numbers: Air Pollution and PM2.5

#51

Post by memonkey »

oh_sigh wrote: post #12
qiqing wrote: post #7

Earlier quoted context omitted.

Do you recommend the air purifier that you have? And would you mind sharing which one has a built-in sensor? I'd like to try measuring my laundry room.

They are expensive, and it doesn't have a built in sensor, but I have an IQAir healthpro compact and have confirmed with my own particle detector that it filters out > 99% of PM0.1 particles, and 100% of PM2.5 particles. If you don't care what it looks like, you can easily build your own air purifier for much cheaper. All it is is a blower fan which forces air through 2 or 3 filters, with the last being a HEPA filter…

IQAir is just a fan, but it isn't just a HEPA filter. IIRC, the bottom filter is a large particle filter (for dust and hair), the middle filter is a carbon filter (for smoke and paint) and the third is a micro particle filter (But yeah, you can easily just put a few dryer sheets on the back of your fan if all you're worried about is large dust and hair particles. The only reason to buy IQAir is if you're paranoid or severely allergic/have health problems.

Re: The Weight of Numbers: Air Pollution and PM2.5

#53

Post by staikken »

sberder wrote: post #50
staikken wrote: post #42

Earlier quoted context omitted.

I've worked for a company that measures PM2.5 in the past. Using a HEPA filter to remove PM2.5 seems unlikely to me. Perhaps there's something more going on here than I've picked up from a quick skim of the site (perhaps there's some sort of cyclonic separation happening) but I'm skeptical this is actually removing particulate at that scale.

I'm not sure I get what you're saying here, HEPA is a standard that was developed for medical environments & clean rooms [1]. To qualify as HEPA, a filter should be able to remove 99.97% of particles 0.3µm and above so it is definitely impacting PM2.5 (particles 2.5µm and below). See my other comment [2] for my opinion on smartair solutions. [1] https://en.wikipedia.org/wiki/HEPA [2] https://news.ycombinator.com/item…

I was under the impression that the filtration efficiency by particle size for such a filter was not a linear relationship.[0] So manufacturing to a lower bound of 3 may not say much for particles even slightly smaller. My estimation of the magnitude of this effect may be off however as this company seems to suggest.

[0]https://www.globalspec.com/learnmore/manufacturing_process_e...

Re: The Weight of Numbers: Air Pollution and PM2.5

#54

Post by sundvor »

sberder wrote: post #47
sundvor wrote: post #32

Earlier quoted context omitted.

That's interesting. We're looking at moving our son to a new school that's right at the corner of two major artery roads in Melbourne, with some 17 000 vehicles passing daily (just on one of them) according to VicRoads. The building doesn't appear to have a HVAC/filtration system. Playground is behind the building, but still has significant back traffic and is inside of 100-300 metres from the main roads. I'm saying…

You should be concerned as many research shows: * leaving close to a busy road raises the risk of early dementia [1] * higher risk of asthma * cardiac arythmia I could go longer but don't want to get too dark For your situation, I think a laser egg from kaiterra is a good machine, you can bring it around and is reliable on the long run. They use a plantower sensor (mentioned in another comment) but have their own fir…

Great response, thanks very much. That's interesting how it's also been linked to cardiac arrhythmia! I'm unable to order a Laser Egg from (no Australian distributors), so would need to source an alternative - unless I go for a freight forwarder.

Re: The Weight of Numbers: Air Pollution and PM2.5

#55

Post by roel_v »

sberder wrote: post #26
qiqing wrote: post #7

Earlier quoted context omitted.

Do you recommend the air purifier that you have? And would you mind sharing which one has a built-in sensor? I'd like to try measuring my laundry room.

Most purifiers on the market with built-in sensors are unreliable to measure. They usually go for cheap IR sensors without flow control. Your results will vary wildly depending on conditions (temperature and humidity affect measurements a lot). I personally like Xiaomi purifiers for their affordability and noise level. If you're concerned about measuring pm2.5 in your space, you should consider buying a good entry le…

Are there air quality meters available at affordable prices (say, <= $100) that can easily be integrated with home automation systems? (like, have an api, or that connect to cloud services so that I can capture the traffic?) Also, any recommendations on outdoor sensors? There have been a few crowd sourced efforts over thale last few years, but I've not been very impressed by them.

Re: The Weight of Numbers: Air Pollution and PM2.5

#56

Post by ljcn »

sberder wrote: post #47
sundvor wrote: post #32

Earlier quoted context omitted.

That's interesting. We're looking at moving our son to a new school that's right at the corner of two major artery roads in Melbourne, with some 17 000 vehicles passing daily (just on one of them) according to VicRoads. The building doesn't appear to have a HVAC/filtration system. Playground is behind the building, but still has significant back traffic and is inside of 100-300 metres from the main roads. I'm saying…

You should be concerned as many research shows: * leaving close to a busy road raises the risk of early dementia [1] * higher risk of asthma * cardiac arythmia I could go longer but don't want to get too dark For your situation, I think a laser egg from kaiterra is a good machine, you can bring it around and is reliable on the long run. They use a plantower sensor (mentioned in another comment) but have their own fir…

Funny to see this 16-bit-plus-one range in the Laser Egg specs:

> PARTICLE COUNT

> 0-65536 particles / 0.1L

Re: The Weight of Numbers: Air Pollution and PM2.5

#58

Post by anarbadalov »

ggm wrote: post #27
anarbadalov wrote: post #2

Undark & the Pulitzer Center visited seven countries on five continents to examine the impacts of particulate pollution on the lives of everyday people, and to uncover what’s being done — or not — to address it. The project is comprised of data visualizations, short narratives, on-the-ground 360-degree videos, an explainer film, and photos from Pulitzer prizewinning photographer Larry Price. What's interesting is tha…

Do you work with the people at QUT (Brisbane) or Floreanopolis (Brazil) doing fine particulate work near airports and in hospitals? my partner did some proofreading and english-as-a-second-language with these people, fascinating stuff (as a complete outsider) and very important.

We don't. While we do often publish stories on public health issues, we don't conduct any of the research, we just report on the science. Australia and Brazil aren't regions we visited for this project, although I wouldn't be surprised to hear that there are areas experiencing extreme events in both.

Re: The Weight of Numbers: Air Pollution and PM2.5

#59

Post by graeme »

SECProto wrote: post #43
graeme wrote: post #22

Earlier quoted context omitted.

My electric stove shoots my AQI through the roof when frying. Made me consider alternate ways to cook. Though, would like to know if gas is worse, as one alternative I was considering was Donabe, which requires gas.

A fume hood that keeps splatters in and vents a lot would work. I think it's just unavoidable that frying vaporizes/aerosolizes particles, so your options are either vent the contaminated air, or don't fry.

So gas that doesn't fry would be ok? Like, making a stew for example. Am wondering if the gas burning itself produces a lot of particulates.

I don't think a fume hood is an option in my apartment unfortunately.

(You can get a single gas burner to cook things in a donabe)

Re: The Weight of Numbers: Air Pollution and PM2.5

#60

Post by gh02t »

graeme wrote: post #59
SECProto wrote: post #43

Earlier quoted context omitted.

A fume hood that keeps splatters in and vents a lot would work. I think it's just unavoidable that frying vaporizes/aerosolizes particles, so your options are either vent the contaminated air, or don't fry.

So gas that doesn't fry would be ok? Like, making a stew for example. Am wondering if the gas burning itself produces a lot of particulates. I don't think a fume hood is an option in my apartment unfortunately. (You can get a single gas burner to cook things in a donabe)

Gas combusts pretty cleanly and doesn't release much.

I personally wouldn't worry about particulates from cooking that much. Get an air purifier if you want, any decent one should be able to pull that stuff out of the air fairly quickly.

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