Smoke, Smog, Dust 2015 Chiang Mai

[Awk]

Member Johnsjourney posted an interesting observation regarding how the pollution level seems to fall quite regularly during each day, thought at the time he posted, we were only a few days into March and he thus did not have so much data available. I updated with data from the aqmthai-site (station 36t), and generated plots similar to what Johnsjourney originally did. These plots show the data from March 1 till 17:00 today (March 10), though I did not smooth the curves like I suspect Johnsjourney did.

As one can see from both the pm10 and the pm2.5 plots, each day the pm-level still falls rapidly in the late morning, remains fairly low for a few hours, and then starts to raise again. Looking at the pm2.5 plot, on most days, the pm level starts to fall at around 12:00 (which means, the average pm-level since time 11:00 has been falling), and is relatively low in the period 15:00 - 17:00 on the graphs.

It is interesting that there is such a clear trend with the pm-levels raising and falling. The aqmthai site (which is pretty damn good, ignorant Thai-bashers not withstanding) also has data for temperature and windstrength (ws), as well as other things I have no idea what is. So I fetched data for some ws and temperature also for the same period. One can then put the different plots underneath each other to see if one can visualize any correlation.

The plot for windstrength (ws) shows a somewhat inverse relation to the pm2.5 plot for part of the time. At around 12:00, ws increases, and remains relatively strong till 16:00, at which the ws starts dropping again. The ws seems to vary quite a bit however, going up and down by a large amount, while the pm-level is mostly constantly going up or down, so I cannot see a good correlation. On both the pm-graph and the windstrength-graph, something does seem to happen each day at around noon however, so presumably there is some relation, though it is impossible to say that one causes the other for me.

The plot for temperature is very regular, much more regular than the pm2.5 plot. As one sees on the pm2.5 plot, there is some variability regarding both when the level starts to fall, and how fast it falls, while this is not present on the temperature graph as far as I can see.

It is difficult to see on the plot, but on day 01, pm2.5 started dropping two hours later than the other days. On this day, the temperature also started out at it's lowest, at 24.5 degrees, and remained lower than for the other days at least until in the afternoon. On this day, the temperature of 38 degrees was also reached two hours later than on the other days.

Have to admit all of the above speculation is very much bush league however, so just thinking a loud here. Perhaps somebody else has some other ideas. It does look to me that the time 14:00 - 16:00 (real time, not the one hour delay on the graphs), or better, 15:00 - 16:00, is generally the least bad time time of day, however. Also not just by a little bit, but by a large factor the best time of day.

pm2.5-raw.pdf

pm10-raw.pdf

temp.pdf

ws.pdf

[Awk]

For those who are lucky to get hold of and afford N95s, FFP-1, KN90, whatever....pls do a proper test-fit. It's the same thing you'd do in a lab or healthcare setting. No proper test fit or care to ensure nearly zero bypass = nearly useless. Technically, you are not supposed to use it for more than a day. But I guess if stocks are low, you can push it to 2 days. It's an electrostatic filter element inside, once it's wet (eg due to human breath with many hours of usage), it's a goner.

Video showing how to wear a N95 properly.

https://www.youtube.com/watch?v=Ul9nbpyPgIw

My personal favourite is the 9210 and 9211 (with exhaust valve). It fits most people almost perfectly due to its soft design. It's also foldable, so it's really convenient to bring it out where it matters most.

The 8210 "turtle shell" actually has 3 sizes, if you are a lady with a small face and you got the large sized 8210, you are as good as not wearing anything due to the horrible amounts of bypass. For older children, you can go for the 1860S or 8110S.

The issue of bypass is very common when N95s are worn by the lay person on the street.

Any decent masks to recommend that can be used for a longer time? I've occasionally been dumping a 3M N95 on a friendly guy who works outside, but if there's something better (basically, more long-lasting, reusable in some way) that is not too expensive or scary looking, I'd perhaps buy that

for him instead next time.

[vivid]

Get the 3M 9913F as it has a carbon layer which removes all smell and volatile vapors. The nice thing about that is that if you can smell smoke, you have a poor seal. With the 9913 you can walk right through a cloud of smoke from a fire and not smell a thing.

Haha....the activated charcoal masks are great. I have the UVEX FFP-2 version (model 3220) and tested it a Chinese temple with huge incense burning, really smelled nothing.

It's not easily available, I got it from taobao, which is the Chinese equivalent of Ebay/amazon. UVEX masks (Germany) should be authentic there, while 3M KN90s are really subjected to many knock-offs.

[T_Dog]

Get the 3M 9913F as it has a carbon layer which removes all smell and volatile vapors. The nice thing about that is that if you can smell smoke, you have a poor seal. With the 9913 you can walk right through a cloud of smoke from a fire and not smell a thing.

Haha....the activated charcoal masks are great. I have the UVEX FFP-2 version (model 3220) and tested it a Chinese temple with huge incense burning, really smelled nothing.

It's not easily available, I got it from taobao, which is the Chinese equivalent of Ebay/amazon. UVEX masks (Germany) should be authentic there, while 3M KN90s are really subjected to many knock-offs.

Ah ha, activated charcoal. I knew I was using the wrong term! I was just in the 3M store on Waluwai Road and they have the 9913V masks in stock, and they also have lots of Filtrete.

[beau thai]

But checking wikipedia (which may be wrong) the USA permitted daily level is 150!! N

No, the allowable is 150 maximum for average in one 24 hour period in a year (365 days). In other words, only 1 day out of 365 is the maximum of 150 allowed. EPA.gov

Hmm- Los Angeles currently showing PM10 of 124 and 'Unhealthy' - at 4 in the morning. Higher later on a 24 hour average?? maybe.

[vivid]

Any decent masks to recommend that can be used for a longer time? I've occasionally been dumping a 3M N95 on a friendly guy who works outside, but if there's something better (basically, more long-lasting, reusable in some way) that is not too expensive or scary looking, I'd perhaps buy that

for him instead next time.

Unfortunately nope.... Even the respirators type of masks need to have their filters changed. The nature of the electrostatic filter element is as such, you just need to change it out regularly.

FFP-1 masks (80% filtration at 0.3 microns) are probably cheaper, UVEX manufactures FFP-1, 2 and 3 grades. I get them from taobao which is the Chinese equivalent of Ebay/Amazon. Each mask is just 40 Singapore cents or so, or about 9 baht? FFP-1 are slightly easier to breathe compared to N95, slightly less resistance.

I also get my 9210 from Amazon, each box of 20 costed me usd4.05 only. Saw the deal on Amazon and got many boxes that time, Singapore enjoys free-shipping if you hit > usd125 in a single order.

[vivid]

BTW, are HEPA air purifiers difficult to buy or expensive in Chiang Mai?

Since the haze seems to be quite a long drawn "battle" on a yearly basis, I think it'd be cheaper and more effective/useful to just get an air purifier. I have like 9 boxes of 3M aircon Filtrete that I have gotten from Amazon. They don't last more than 2-3 weeks in my aircon and that's in clean air here in Singapore during the non-hazy months. Someone used it during the hazy days last time and he said you can discard it after 3-4 days.

I have a laser particle counter that displays both mass and particles per L, with an air purifier that's properly sized, I can get an ambient of PM2.5 40ug/m3 down to 0 in my bedroom within half an hour.

Eg, I got my Samsung AX40 air purifier direct from Korea, it's like 6200 baht inclusive of shipping. 323m3/hr machine, 34W, 45dB noise that's great for light sleepers. A Sharp A28 costs 2300 baht only.

I use HEPA filters from China as replacements, they are pretty ok....like about 95-98% efficient @ 0.3 microns. About 230 - 460 baht per piece. I source them from taobao, the Chinese equivalent of Ebay/Amazon.

[CNXBKKMAN]

With all the smoke in the air at around 18:00 i took this photo of the sun from CM city centre. 50x magnification and no chance of being blinded!

When i looked at the image there is a sun spot.

[Awk]

BTW, are HEPA air purifiers difficult to buy or expensive in Chiang Mai?

Since the haze seems to be quite a long drawn "battle" on a yearly basis, I think it'd be cheaper and more effective/useful to just get an air purifier. I have like 9 boxes of 3M aircon Filtrete that I have gotten from Amazon. They don't last more than 2-3 weeks in my aircon and that's in clean air here in Singapore during the non-hazy months. Someone used it during the hazy days last time and he said you can discard it after 3-4 days.

I have a laser particle counter that displays both mass and particles per L, with an air purifier that's properly sized, I can get an ambient of PM2.5 40ug/m3 down to 0 in my bedroom within half an hour.

Eg, I got my Samsung AX40 air purifier direct from Korea, it's like 6200 baht inclusive of shipping. 323m3/hr machine, 34W, 45dB noise that's great for light sleepers. A Sharp A28 costs 2300 baht only.

I use HEPA filters from China as replacements, they are pretty ok....like about 95-98% efficient @ 0.3 microns. About 230 - 460 baht per piece. I source them from taobao, the Chinese equivalent of Ebay/Amazon.

January last year I shopped around in CM for air purifiers. There are various price ranges of air purifiers available, from cheaper Korean brands (Samsung), or even the Chinese Hatari which I also think I saw somewhere, to more expensive stuff from Canadian Bionaire, and some European brand also if I remember correctly.

From what I read, some air purifiers give of ozone or other harmful things, so I wanted to get one that had been tested by something reputable to not do that. I'm sure I paid way over the top, but I bought Blueair, ordered from Bangkok as I could not find it locally in Chiang Mai. Phillips also had a model available in Thailand with good reviews, but the price difference was not too big compared to the comparable Blueair model I was looking at.

Basically Blueair (and IQAir, also available in Thailand I think) was in the top 3-5 of any test I found, Consumer Reports USA included, if reviewed at all. At the time I was getting very bored with spending a lot of time trying to cross-check air purifiers I could find in the various local shops here against reviews on the net, so just caved in and bought what I assumed was some of the best I could get.

After testing (with the Dylos) both 3M filtrete and the air purifier, getting an air purifier was a no-brainer for me, though that was based on efficiency only, not price. With your calculations, it looks like one of those air purifiers will be cheaper also, even in the not so long run.

The replacements for my Blueair model were 7,000B last I checked, scheduled for replacement after 180 days it says, so the calculation is a little different there.

The Blueair model I got (650) is speced for > 765m^3/hour, but even this one I have to run at the max power in the bedroom these days. Generates an awful amount of noise, which surprisingly enough does not prevent anyone from falling a sleep. Even at that setting, the Dylos reports pm2.5 readings up to 4000 now though. Still, that's a tenth of what is outside the very poorly isolated room, so it seems to be doing its job.

[Tywais]

From CM108 near 700 Stadium. More photos CM108 Google Translate (Photos by the Community Ariya Non).

[Tywais]

And the snapshot of the firemap shows a high density of fires now, more than in any previous snaps. Crazy. March 10, 2015

[nikster]

From CM108 near 700 Stadium. More photos CM108 Google Translate (Photos by the Community Ariya Non).

Looks like that might be in Burma! Just saying.

555

Hey does anyone know (and excuse me if it's been covered already) about this website: http://aqicn.org/city/chiang-mai/

It looks fancy, it shows up in Google, and it also reads a "PM10 AQI" (note the aqi!!!) value that's 100 points lower than actual, even as the site claims to use the official values as a data source. (official is 234 as of posting time)

[vivid]

Good morning folks!

Hi awk, good to see a fellow air purifier enthusiast here. Will reply in detail soon, going to work.

Looks like that might be in Burma! Just saying.

555

Hey does anyone know (and excuse me if it's been covered already) about this website: http://aqicn.org/city/chiang-mai/

It looks fancy, it shows up in Google, and it also reads a "PM10 AQI" (note the aqi!!!) value that's 100 points lower than actual, even as the site claims to use the official values as a data source. (official is 234 as of posting time)

Hi nikster,

aqicn is using PM10 AQI, an index (there are many other indexes used by other countries like Australia, Singapore, Malaysia, but basically it's just an index for the layman to understand. aqmthai is using ug/m3, a raw data concentration figure that is commonly used to denote concentration of something.

This is a 24-hr rolling average figure, same as other countries. In Singapore, we also get 1-hr ug/m3 and also a 3-hr rolling average PSI index figure. Hence, a 24-hr rolling average is just one of the figures that shows you one part of the picture.

aqmthai also has 1-hr ug/m3 concentration figures published

Here : http://aqmthai.com/public_report.php

Please use this to convert PM2.5 or PM10 concentration figures to AQI index. AQI index is used by China and the USA (and some other countries probably).

And yes, 234 ug/m3 PM10 = AQI 140. This is what is reported on aqicn.org.

http://airnow.gov/index.cfm?action=resources.conc_aqi_calc

Occasionally, I also use the 1-hr PM2.5 concentration figure and convert to the AQI figure. Officially, it's to be used for 24-hr figures only. However, in Singapore, the official agency also use this to derive their 3-hr rolling average figure with the same breakpoints, they mentioned this is to give a faster and more accurate figure that'd denote what's happening on the ground.

Anyway, an index is just an index. Likewise for ug/m3.

It's well over PM2.5 268 ug/m3 for station 36t at 0600h, which is very high and it's still climbing (will con't to climb). Second point is that starting from March 8th 0300h early morning, the levels have been high to very very high. 3-days 72hrs.

Folks, please take care and reduce exposure. Do not treat this lightly.

[evenstevens]

righr on our own doorstep, where are the myarmar theorists

over many years have witnessed such fires out in beverly hills,maerim and futher up north this pic, is mere brush fire

they can smoulder for a eternity

rain is our only hope, just hope the pilots of the rain making plane , remember to fill up their gas tanks

very surprised that the airport has not been closed

[khwaibah]

righr on our own doorstep, where are the myarmar theorists

over many years have witnessed such fires out in beverly hills,maerim and futher up north this pic, is mere brush fire

they can smoulder for a eternity

rain is our only hope, just hope the pilots of the rain making plane , remember to fill up their gas tanks

very surprised that the airport has not been closed

Thais could never do this.

[dutchkev]

Does anyone know how far south u have to go to get cleaner air?

[vivid]

Does anyone know how far south u have to go to get cleaner air?

From the available data, to be really sure, i am guessing as far south as BKK.

Chiang Mai 0900h PM2.5 = 301ug/m3

Over here in Singapore, we start to freak out from about 60 ug/m3! . Last night, my region got down to as low as 1 ug/m3 pm2.5.

[beau thai]

From CM108 near 700 Stadium. More photos CM108 Google Translate (Photos by the Community Ariya Non).

Great photo-and just look at all that cr*p above the flames going into our atmosphere. Absolutely crazy.

Every year the government talks and wrings its hands and every year nothing changes.

What will it take when the wil to change doesn't exist?

[Konini]

Hey does anyone know (and excuse me if it's been covered already) about this website: http://aqicn.org/city/chiang-mai/

It looks fancy, it shows up in Google, and it also reads a "PM10 AQI" (note the aqi!!!) value that's 100 points lower than actual, even as the site claims to use the official values as a data source. (official is 234 as of posting time)

I've seen this site mentioned several times in previous years, and for the first time I've actually looked at it. I zoomed out on the map and found Delhi to be 895! Even taking the 100 points off, If the air there is several times worse than ours, surely they'd all be dead wouldn't they?

I know it's very, very bad right now, but this is making me a little sceptical of the numbers.

[vivid]

I've seen this site mentioned several times in previous years, and for the first time I've actually looked at it. I zoomed out on the map and found Delhi to be 895! Even taking the 100 points off, If the air there is several times worse than ours, surely they'd all be dead wouldn't they?

I know it's very, very bad right now, but this is making me a little sceptical of the numbers.

Hi,

Pls check out my reply this morning at 0828h. I have explained it in detail.

Aqicn is correct.

[wisemonkey]

This is my first time going through smokey season in chiang mai, the first few weeks I thought 'what was all the fuss about, nothing too bad at all', the last 7 days changed that,.. visibility is very low, not to mention the health repercussions of all this dust/ash/dirt going into your lungs.. I wonder if this is something that will be weeded out in the next decade or so as thailand continues to develop. I would understand if it was necessary burning, for the farmers to make a living, however it does not seem like this is the case, right next to our mooban I got a family with rice paddies who were just burning up old weeds and dead plants, not to mention throwing on plastic rubbish onto the fire just to add that extra little bit of toxicity.

[MastaMak]

As far as I know I've never heard anyone blaming it on Burma (outside from the media). What I've heard and is shocking is "let them continue the burning, otherwise we won't get the burning compensation money from the government".

Also I think most burnings are for the mushrooms, it is pretty obvious that they aren't burning only fields, but the whole mountains.

[EnlightenedAtheist]

It is okay, folks! If you believe, you will be reincarnated! JUST BELIEVE and go to the temple! Or, if you are rich, go to the beaches ... and go to the temple for others ... and you!

[MastaMak]

I've seen this site mentioned several times in previous years, and for the first time I've actually looked at it. I zoomed out on the map and found Delhi to be 895! Even taking the 100 points off, If the air there is several times worse than ours, surely they'd all be dead wouldn't they?

I know it's very, very bad right now, but this is making me a little sceptical of the numbers.

This is probably a bug. This site / app is based in China and the max level is at 400. It doesn't show over 400 as it is China and therefore biased, Chinese officials don't allow to show over 400.

[vivid]

This is probably a bug. This site / app is based in China and the max level is at 400. It doesn't show over 400 as it is China and therefore biased, Chinese officials don't allow to show over 400.

I have seen AQI 600 to 800 for Harbin and Beijing etc. PM2.5.

The chinese have other sites too, eg pm25.org.cn....and they do show above 400.

China does censor, but not for this.

Hope that helps.

[vivid]

May I post again with regards to PM2.5 being the more important point to take note of (at least for the current situation) in Chiang Mai.

Station 36t in CM has 1-hr PM2.5 concentration data published. You can define a 24-hr search to get the average.

Lets take 251 ug/m3. The risk for PM2.5 is much higher than PM10 at the same concentration.

Pls take note of the PM2.5 figures.

The same thing happened in Singapore before we adopted PM2.5 being a main pollutant to be included in the PSI index very recently.

The same thing happened between Beijing environment ministry vs US Embassy before Beijing authorities adopted the PM2.5 standard. The 2 health advisories were always like a day and night difference.

You can read about it all here :

https://www.chinadia...rder=old&page=2

http://www.ebeijing....te/t1212024.htm

But that is not to say that PM10 is useless. In dust storms (bigger particulate matter), PM10 would form the dominant pollutant and not PM2.5.

PM10 also does not travel as far as PM2.5 (PM2.5 can travel for close to 2000km in Indonesian biomass haze)

Perhaps pictures would best illustrate it :

[vivid]

This is probably a bug. This site / app is based in China and the max level is at 400. It doesn't show over 400 as it is China and therefore biased, Chinese officials don't allow to show over 400.

I have seen AQI 600 to 800 for Harbin and Beijing etc. PM2.5.

The chinese have other sites too, eg pm25.org.cn....and they do show above 400.

China does censor, but not for this.

Hope that helps.

Got the pic. 788 and 827 respectively for PM2.5 and PM10.

[Tywais]

China does censor, but not for this.

A few years ago the Chinese government made a fuss because the US Embassy had their own monitoring equipment and was warning the US citizens of the danger. Perhaps the Chinese government has decided to come clean now.

[Tywais]

From CM108 near 700 Stadium. More photos CM108 Google Translate (Photos by the Community Ariya Non).

Great photo-and just look at all that cr*p above the flames going into our atmosphere. Absolutely crazy.

Every year the government talks and wrings its hands and every year nothing changes.

What will it take when the wil to change doesn't exist?

The irony of it is that the Chiang Mai governor's office is very close to this.

[Mapguy]

May I post again with regards to PM2.5 being the more important point to take note of (at least for the current situation) in Chiang Mai.

Station 36t in CM has 1-hr PM2.5 concentration data published. You can define a 24-hr search to get the average.

Lets take 251 ug/m3. The risk for PM2.5 is much higher than PM10 at the same concentration.

Pls take note of the PM2.5 figures.

The same thing happened in Singapore before we adopted PM2.5 being a main pollutant to be included in the PSI index very recently.

The same thing happened between Beijing environment ministry vs US Embassy before Beijing authorities adopted the PM2.5 standard. The 2 health advisories were always like a day and night difference.

You can read about it all here :

https://www.chinadia...rder=old&page=2

http://www.ebeijing....te/t1212024.htm

But that is not to say that PM10 is useless. In dust storms (bigger particulate matter), PM10 would form the dominant pollutant and not PM2.5.

PM10 also does not travel as far as PM2.5 (PM2.5 can travel for close to 2000km in Indonesian biomass haze)

Perhaps pictures would best illustrate it :

Excellent post and worth quoting.

It is important to understand the difference between PM<10 and PM<2.5 standards because it is PM<2.5 pollution that has the really serious effect on health. The difference in impacts on short and long-term exposure on health are actively researched. That can be Googled.

Standards do vary from country to country as to the different effects on health. Some prefer American EPA, EU, WHO standards, and some prefer some easier standards, which are a perverse reflection as to what is achievable, given national circumstances, in targets for reduction.

Looking locally, one discomfiting result of research on burning rice straw is that the concentration of PM<2.5 is higher than the "norm" of 40 - 60% of PM<10. You won't be pleased with comparing the two standards as reported at Site 36T, Chiang Mai, where data for PM<2.5 is reported, an innovation this year.

To the governor: Think globally, ACT locally!