Air Quality Monitoring in Bangkok - What's your PM 2.5 ?
Air4Thai app screenshot, showing air quality at different locations in Bangkok
Air Quality Alert
Bangkok is known to have a very limited number of public parks. Fortunately, off the main streets, trees can still be found along the streets and in private properties. However, empty plots are slowly but surely disappearing, with people moving out to the outskirts of the city, and property developers moving in.
We are near to the end of the cold season in Bangkok, en for about three weeks now the air quality in Bangkok and surroundings has been covered regularly in the English-language newspapers in the city. This is unusual. Actually, the 'common' knowledge now says that the environment now is considerably better than some years ago.
On 8 February 2018 there was a quite visible haze over Bangkok, not only in the far distance and when looking towards the sky, but also when looking at nearby high-rise buildings. The same day the Pollution Control Department issued a warning that unhealthy levels of particulate matter would make life a bit uncomfortable for a few more days. That day PM 2.5 (smaller than 2.5 microns) levels ranged between 69 and 95 microgrammes per cubic meter during most of the day. We recall that these small particles are most likely to be settling in the lungs and cause all kinds of havoc in the body. The Environmental Protection Agency states that levels lower then 50 microgrammes are 'satisfactory', though as far as we know it is a case of the lower the better. More than 150 microgrammes is 'very unhealthy', and the values in between are unhealthy. Of course, people with underlying diseases will always be at risk earlier.
The EPA of the U.S. states that higher levels can cause : premature death in people with heart and lung disease, nonfatal heart attacks, irregular heartbeat, aggravated astma, decreased lung function and increased respiratory symptoms. Personally, we noticed some stinging in the eyes when walking outside.
Interestingly, PM 2.5 levels are not regularly reported by the Thai Pollutions Control Department. We recommend using the App provided by the department ( called Air4Thai ) which provided a few times a day updated measurements of the Air Quality Index, which apparently is based on PM 10, ozone levels, and on a number of gases in the air such as CO and NO2 . There are measurements from a number of locations around Bangkok, but now from interesting areas such as Sukhumvit Road or Silom Road. Rama IV road measurements are probably those closest to the center.
But you can also check out various provinces in Thailand. This is especially important before embarking on the trip to the Chiang Mai area and the North, which suffers from a bad environment during part of the cold season months (pollution by slash and burn practices).
(partial) Screen Shot of results of air quality monitoring with Acer AM100
Do your know your 'personal' PM 2.5 level ?
It may be useful to have an idea about the air quality at your own location, and also especially your indoor air quality, since that is where you spend most of your time. We have looked into this from time to time, but consumer goods measuring air quality have not clearly been available at an affordable price until recently. However, this year you clearly have a choice of small appliances available. We searched on a popular online shopping site, and noticed a range of small non-branded devices (or at least not from well known brands) produced in China. Quite understanbable, since there most be a big market in China now, what with the recurrents problem of severe pollution in its major cities.
A further search online, and we found a well designed product by Acer, named AM100, which we bought for about 200 U.S. Dollar, transport and immigration costs included from Amazon, when it was priced as a promotion. We checked later on and now it is sold at about 250 U.S. Dollar.
It measures about 10cm x 10 cm x 4.5 cm and provides quite a few data : PM 2.5 levels, PM 10 levels, TVOC (Total Volatile Organic Concentrations) level, and derived from that CO2 Equivalent Value level. (this latest level is not directly measured). You set it up with your home Wifi, and connect to it with Bluetooth. When connected to Wifi, it will relate the measurements to the 'cloud' and you will be able to see some graphs with average hourly results etc. When you go outside and use only Bluetooth (you can of course elect to connect to another Wifi, but that would be a bit laborious to do each time you move), you still can make measurements, but they will not be stored in the 'cloud'.
On 8 February we put the device on our balcony outside and in the morning we got some PM 2.5 levels starting from around 95 microgrammes per cubic meter, slowly decreasing to about 40 microgrammes per cubic meter in the late afternoon. Note : the manual states that the device might be less reliable when used outside, but we think also from other observations that it works well enough. Acer also uses recommended values that are lower than the ones mentions above by the EPA. You should strive to have measurements below 15 microgrammes per cubic meter to be in the 'good' category.
Not to worry too much : When measuring inside our apartment, we usually find levels in the 5 to 15 microgrammes range. When we start using our air conditioner, the first 15 minutes or so, the level may be in the 15 to 30 microgrammes per cubic meter range. This probably means we should have it cleaned. A puzzling problem (at least for me) are the levels of 'Volatile Organic Concentrations' which sometimes are too high (unhealthy for sensitive persons). We have not yet figured out what causes these higher levels (it can come from a variety of 'gases' lurking around your home such as paint components, cleaning products, cooking, etc.). The device picks up 'scents' very easily. For instance, we cleaned our eye glasses with a German produced impregnated tissue, and the TVOC went through the roof for a few minutes. When airing the room, the TVOC usually goes down (generally TVOC levels are lower in the outside air than in the inside air)
Improving the Indoor Air Quality
Hatari Air Purifier ( HT-AP 12 )
We have been preoccupied with our indoor air quality for many years. Actually much more so than with the outdoor air quality in Bangkok. The reason is that for many years we have been heavy smokers. Filtering the air, we figured, may at least reduce the levels of indoor pollution (difficult to open windows in the heat of Bangkok most of the time).
For this purpose, over the years, we have bought a number of air purifiers with HEPA filters and carbon filters. The HEPA filters are supposed to get rid of small particles such as PM 2.5 and PM 10 . We used these air purifiers blindly since up to now, we had no way of measuring indoor air quality. By the way, you can buy air purifiers all around town, especially in the department stores. There are a few problems : they are expensive (twice the price of what you would pay in U.S. or Europe), and even more important, there is an issue with obtaining replacement filters. Simply put, it is easy to buy an air purifier, but one year later you may not find an adequate replacement filter because the department store does not supply it anymore or never did in the first place (especially when newer models of air purifiers have replaced the older models).
The best air purifier we ever had was a brand called SCANA, made in Koreas. Unfortunately, they have disappeared from the market.
But now, since a year or two, the local Thai company HATARI, produces an air purifier, at a very reasonable price of less than 5,000 baht. (HEPA) Filters (always buy them in bulk with your original purchase, to be on the safe side!), are sold at a price below 1,000 baht. You can find them at HomePro, and we found out they work well enough.
How do we know? When we switch them on, they lower the levels of small particles reliably. Within 15 to 30 minutes, levels of PM 2.5 will usually go down to 1 or 2 microgrammes per cubic meter, and levels of PM 10 likewise to between 1 and 4 microgrammes per cubic meter.
TVOC is a different matter. When values are low or moderate, no need to worry. When higher, these filters (also the SCANA air purifier mentioned above), have only a modest and slow effect (if any). You are better off opening your windows for awhile, this may be more efficient.
Acer AM100 Air Quality Monitor
In conclusion, nowadays your can access overall air quality levels around Bangkok and Thailand be using the ' air4thai' app by the Pollution Control Department of Thailand. You can measure your personal environment with a device such as the Acer AM100 Air Quality Monitor. And you can efficiently lower levels of small particles at home with an HEPA-filter equipped air purifier.
P.S. : We do not have any commercial arrangement with either Acer or Hatari, just providing hopefully useful info here.