PM 2.5 meter?

[FolkGuitar]

4 hours ago, motdaeng said:

i hope you want tell us, 7 cigarettes a day for a few weeks (it more 3 months) woudn't do any harm to a newborn / child / elderly person ...  ????

 

Are your reading skills that poor? 

Hey, I'm sorry that this air quality situation upsets you more than it upsets me. But that's not my problem. You are certainly free to get all worked up about it, froth at the mouth, and bitch and moan if you wish to.

Edited March 20, 2019 by FolkGuitar

[thedemon]

On 3/18/2019 at 10:46 AM, vivid said:

I suspect that there are 2 actions that are going on in an enclosed room with airconditioner.

 

1. The water condensate on the aircon coils do clean the  air haze particulates.    And it's a somewhat "decent" device as the evaporative coil is of a good size wrt room size.  

 

2.  There is also natural decay of PM2.5 due to some action of them clumping together or what, i might be wrong with that description but there is indeed some decay over time.  Even in a normal room without an AC, the PM2.5 slowly decays over time.

Of course, with people in the room with closed doors and windows, there will be CO2 buildup, and so when you open the doors/window in exchange for fresh air, it'd shoot back up.

 

If I remember correct my personal measurements, it dips around 20-30% in an AC room.   Not really enough, i guess.

Even a 3M Filtrete electrostatic filter on the FCU (max fan speed please) +  another fan with 3M Filterete stuck at the back works way better than this.

 

 

 

My brief experience would say that you are right. For the past week or so I have been trying out one of the Xiaomi Smart Air Quality Monitors in my bedroom. If I put the unit outside on the window ledge, mostly it records approx 35 PM2.5.

 

Inside the bedroom with the AC running it is stable at 8-12 PM2.5. There are no other filters or air purifiers operating.

 

I have no prior experience with these devices but am surprised that only an AC could reduce the PM2.5 by that much. 

 

[vivid]

9 hours ago, thedemon said:

 

My brief experience would say that you are right. For the past week or so I have been trying out one of the Xiaomi Smart Air Quality Monitors in my bedroom. If I put the unit outside on the window ledge, mostly it records approx 35 PM2.5.

 

Inside the bedroom with the AC running it is stable at 8-12 PM2.5. There are no other filters or air purifiers operating.

 

I have no prior experience with these devices but am surprised that only an AC could reduce the PM2.5 by that much. 

 

 

Wow....that's quite a fair drop.  Maybe i didn't get as much a drop due some other factors.  But it'd drop.   Best is still to get an air purifier / electrostatic filter inside as much as you possibly can, as i reckon it gets cold at night there and so there's a limit as to how much condensate the AC can generate by setting the thermostat so low and trying to operate the compressor as close to 100%.  (gonna be freezing! ????)

 

The good thing is that the levels have come down a lot in Chiang Mai.  Other areas, depends on your location, generally there are significant improvements but most areas at the extreme north are still fairly smoky.

Edited March 20, 2019 by vivid

[Trujillo]

So getting one of these meters is like getting a Breathalyzer, right? 

You know you're totally blitzed, but you want a gizmo that says just how blitzed you really are, on a scale. 

[vivid]

17 minutes ago, Trujillo said:

So getting one of these meters is like getting a Breathalyzer, right? 

You know you're totally blitzed, but you want a gizmo that says just how blitzed you really are, on a scale. 

If you are really interested and have a use for it in the house eg you have infants/young kids/elderly, then go ahead and get the cheapest one, it has to be a laser particle counter module in it though, not those IR diode setups.  

 

If not, just use the money in getting more air purifiers and replacement filters  ????

[vivid]

Here's some pics to share.

 

3 air purifiers operating.  Windows have double rubber gaskets so no issue there.  Slight air exchange at the door gaps (keeps CO2 concentration to sane levels).

Laser particle counter, sensitive down to 0.5 microns according to specs.  In any case they also display a 0.3 reading.

It's not going to be absolutely accurate, but just to show the sensitivity especially at the lower end, near single digit ug/m3.

 

External air quality load.

40k+ particle counts per L

>

 

In the filtered room. 420 counts/L @ 0.5 microns

 

 

At the output of my MFresh M8088A with H12 filter. 10 counts per L @ 0.5 microns. 30 counts/L @ 0.3 microns

 

 

At the output of my Sharp with H11 grade DIY filter (cut to size, 1 side stuffed with air bubble packaging to plug up the gap as it's short of 20mm).  120 counts/L at 0.3 microns.  20 counts at 0.5 microns.

 

 

There is also another Samsung air purifier rated at 330m3/hr (but output is probably in the mid 200 m3/hr range, it's relatively silent even at that output) with H11 filter.

 

 

[vivid]

BTW, i am not in Thailand.   This relatively cheap device still enough sensitivity/very fine gradation to reliably let you measure the difference between filtered air in the room, the very small but measurable output difference between my Mfresh M8088A with original filter vs Sharp with cheap-ass DIY HEPA filter gotten from China Taobao.

 

More than usable enough for our "home use", even though it's not going to be absolutely accurate.

It's like having a digital thermometer that gives you a readout like 35.125, 35.136, 35.137 deg C, or  digital multimeter like 3.7121, 3.7122,. 3.7123 volts for those dealing with Li-ion 18650 batteries.  ????

 

The commercial and expensive lab laser particle counters (eg TSI, MetOne) would have even much finer gradations and sensitivity esp at the low end (maybe 0.1 microns even for top-end models) for use in the cleanroom. 

They would be overkill for "home use", though over here in my country there are a number of expensive MetOne portable devices being used to demonstrate a certain brand air purifier able to drop the particle counts to extremely low levels in an enclosed box and subsequently letting you open and close the box via an opening to let you introduce external air in and seeing the particle count shoot up into the tens or hundreds of thousands @ 0.3 microns. 

 

Just for the demo and sales i guess, doesn't matter at all in reality as we'd then look at the particulate matter and formaldehyde CADR (which also defines overall TVOC CADR and depending on which type of VOC you are attempting to deal with), noise level across various fan speeds, electrical consumption across various fan speeds, size, design, replacement filter availability and cost.  That's also why I DIY my own H11 filters as i replace them every 6 months.

Edited March 28, 2019 by vivid

[vivid]

One more picture regarding cheap PM2.5 laser particle counters from China.

 

[THAIJAMES]

I noticed that xiaomi now has a portable one for about $30. 

I think the only difference between this one and the other more expensive one is it has no Wi-Fi and therefore you can't connect their app.

 

Almost no reason for everyone not to have a sensor in their home.

Edited March 28, 2019 by THAIJAMES

[THAIJAMES]

1 hour ago, THAIJAMES said:

I noticed that xiaomi now has a portable one for about $30. 

I think the only difference between this one and the other more expensive one is it has no Wi-Fi and therefore you can't connect their app.

 

Almost no reason for everyone not to have a sensor in their home.

US $28.27  19%OFF | Xiaomi Mijia Smartmi PM2.5 Air Detector Portable Sensitive Mijia Air Quality Tester LED Screen Three-color Digital Indicator
https://s.click.aliexpress.com/e/juGQ1RS

 

[sfokevin]

On 3/20/2019 at 6:30 PM, thedemon said:

For the past week or so I have been trying out one of the Xiaomi Smart Air Quality Monitors in my bedroom. If I put the unit outside on the window ledge, mostly it records approx 35 PM2.5...

If your ledge is in Chiang Mai I would say there is something wrong with your monitor... 

 

[thedemon]

2 hours ago, sfokevin said:

If your ledge is in Chiang Mai I would say there is something wrong with your monitor... 

 

 

No, my ledge is not in Chiang Mai but going by your post, it seems that you may not know the difference between AQI and PM2.5. Have a look: AQI Calculator

 

I normally live in Bangkok, having moved there in my early twenties. Now almost 30 years later and in my early fifties I have zero respiratory problems and no health issues that I know of. I've only taken any notice of the whole PM2.5 issue from reading on this forum which is what caused me to buy some detectors and install some apps incl the airvisual one you showed.

 

So today I land in Auckland, NZ and immediately drive to Hamilton (approx 150km south) and this having not yet uninstalled the annoying airvisual app, this is what I am presented with;

 

 

Now if this was a boredom index, I believe Hamilton would score quite well. But it isn't, instead I am to believe that the potential health damage from pollution in Hamilton NZ is about the same as Bangkok and much worse that Phuket. 

 

Nah, I've got bigger fish to fry than this BS.

 

[sfokevin]

11 hours ago, thedemon said:

No, my ledge is not in Chiang Mai but going by your post, it seems that you may not know the difference between AQI and PM2.5. Have a look: AQI Calculator

I live in Chiang Mai and sadly am very well educated on the way the AQI is calculated... And one day hope a monitor on my window ledge will read 35 meaning an AQI of less than 100... 

 

Edited March 29, 2019 by sfokevin

[vivid]

12 hours ago, thedemon said:

 

I normally live in Bangkok, having moved there in my early twenties. Now almost 30 years later and in my early fifties I have zero respiratory problems and no health issues that I know of. I've only taken any notice of the whole PM2.5 issue from reading on this forum which is what caused me to buy some detectors and install some apps incl the airvisual one you showed.

 

Now if this was a boredom index, I believe Hamilton would score quite well. But it isn't, instead I am to believe that the potential health damage from pollution in Hamilton NZ is about the same as Bangkok and much worse that Phuket. 

 

Nah, I've got bigger fish to fry than this BS.

 

 

You are not wrong when talking about long-term/chronic respiratory issues or having stroke/heart attack increased risks (that's never going to be 100% also), that is because BKK's air quality isn't that bad to start with.   In 2018, Bangkok’s PM2.5 particulate pollution averaged 27µg/m^3.

 

It's just a bit higher than Singapore's 17-18 ug/m3 on years where there were not much haze.  27-28 ug/m3 is what we get here in Singapore during the serious hazy years ie 2015 we had 28 ug/m3 annual.

 

The transient 1-3 hr spikes in air quality all the way to 24 or a few days main concern is triggering symptoms of various severity with those who already have a medical issue like asthma, rhinitis/sinusitis, asthma, lung diseases.  For normal pax it might be "just" a headache, some nausea, some running nose/cough/sore throat, sore/dry eyes and general lethargy....some paracetamol and antihistamines, cough mixture and mulcolytic/expectorants, eye drops should sort those out.  The increase in stroke/heart attack risk for normal pax and even for those in the susceptible group like elderly and with some other related health risks like HBP is not 100%.

 

 

So it really depends on how you see things and value stuff in life.   Some people smoke and tell ya there ain't no issues, and some people won't even go near it.  Similar to other stuff like having a high sugar intake, would it cause a health issue in you later on, age 40, 50, 60? Other than type 2 diabetes, how about cancer/heart attack due to inflammation risks? Personal choices.

 

Like i was saying in another thread that a $5 HEPA DIY filter from China works ok too in the air purifier (not talking about pasting those HEPA filters in front of a box fan, far too low a CADR) if you wanna save some money with regards to Particulate matter filtrationas as some original filters (Sharp/Samsung) really cost an arm and a leg esp if you are replacing them once every 6 months due to heavy filter loading , that "HEPA" sealing doesn't matter that much in real life as we are not dealing with a vacuum cleaner here (very different in operation and usage vs a Air purifier filtration device). 

 

 

So it really depends on the individual.  In short, i think it's best to lower intake of say PM2.5, PM10, sugar, trans fats etc......but don't live your life until drinking a 500ml bottle of Coke becomes a total sin that you can't get to sleep at night.

edit - ok i am just kidding, it really depends, a healthy pax can drink that 500ml bottle of Coke, but a prediabetic/diabetic better not drink that.   ????

 

PS. Bonus picture, i ever tried 3000+ ug/m3 before, nearly 5 mins of it.   Survived though, with a very very itchy airway.  ????

Edited March 29, 2019 by vivid

[vivid]

Anyway, does anyone know what is Chiang Mai's annual PM2.5 concentration?

 

IIRC, I read some link before that they measured around 40+ ug/m3 PM2.5.    But that isn't PCD figures, just some research literature i think.

 

These official figures aren't too easy to find, as govts don't like to "advertise" in the wrong way, if you know what i mean.

[vivid]

Actually talking about sugar intake, i am someone that has a rather high intake of carbohydrates and sugar.   (i have a rather sweet tooth).  

I'm trying to limit my intake, but lets just say that a daily slice of cake or dessert and some 300ml of soda (or more!) is definitely a must for me.  Yeah you can say that i am addicted to sugar.  ????  I just so happen to be very mindful about this as well because my father is a diabetic and my father in law is a prediabetic, and i do value my health as local healthcare costs a bomb, esp for these chronic issues.   I do my own OGTT/oral glucose tolerance test with their blood glucose meters and my 75g 2-hr OGTT blood glucose readings is actually better than their 8hr FASTING blood glucose reading.

 

Then again, i don't lead a sedentary lifestyle and is somewhat active daily....no i am not some exercise or gym freak or what, like i just don't sit down and watch TV right after dinner, and if there is any chance for me to walk 1-2km from the metro station to my house or take the stairs, i'd do it.  I am also nowhere near fat or obese.

 

So ultimately as with any health issues, YMMV, your mileage may vary, depending on who you ask.

 

 

Edited March 29, 2019 by vivid

[THAIJAMES]

6 hours ago, vivid said:

Anyway, does anyone know what is Chiang Mai's annual PM2.5 concentration?

 

IIRC, I read some link before that they measured around 40+ ug/m3 PM2.5.    But that isn't PCD figures, just some research literature i think.

 

These official figures aren't too easy to find, as govts don't like to "advertise" in the wrong way, if you know what i mean.

I would also be interested in this