Click the button to check the Chiang Mai pollution levels TODAY! It’s getting to that time of year again when the pollution levels in Chiang Mai start climbing to dangerous levels. This happens every year towards the end of the dry season, between February and April and is largely attributable to slash-and-burn farming methods. Last year the pollution levels got so high that literally thousands of people across Chiang Mai province were admitted to hospital with various respiratory illnesses – including Tina – and the government released a 24 hour emergency number for reporting the fires. You can view the pollution levels in Chiang Mai between 1998 and the present day by clicking on the button above.
PM10 – small but deadly particles
One of the measurements to look for is the PM10 (PM-10) level. This indicates the density of very small particulate matter in the air (particulate matter less than 10 microns in diameter in a cubic metre of air). These particles are too tiny to see – five particles would fit across a strand of human hair – but they can be deadly. As an illustration of how dangerous these particles can be, the number of people in a seemingly ‘clean’ country such as New Zealand who die early from pollution caused by traffic is similar to the number killed in road accidents each year.
These small particles of pollution in the air come from sources such as waste burning, wood burners, car exhausts and industry. They can cause serious health problems, such as making breathing problems like asthma and bronchitis worse. They can exacerbate heart problems, and are thought to be one of the catalysts for throat & lung cancer.
In London, the United States and the European Union as a whole it is considered a serious pollution ‘episode’ if the PM-10 level exceeds 50 – see the London Air Quality Network website.
For some reason, the Thai Pollution Control Department has set the ‘safe level’ to be anything less than a PM-10 of 120. Just to illustrate how high the levels can get to in Chiang Mai, on 14th March 2007 PM-10 levels reached 303.9 – catastrophically high by any standards.
By way of a comparison, the World Health Organisation came up with weighted list of average PM10 concentrations in residential areas of cities larger than 100,000 throughout the world, and the averages were as follows:
A selection of these is as follows:
- China – 87
- Denmark – 23
- France – 15
- Germany – 22
- Greece – 47
- Indonesia – 102
- Iraq – 178
- Israel – 52
- Malaysia – 24
- Myanmar – 89
- New Zealand – 16
- Pakistan – 180
- Saudi Arabia – 106
- Spain – 40
- Sudan – 246
- Syria – 102
- Sweden – 13
- Thailand – 76
- United Kingdom – 19
- United States – 25
I decided to work out the daily average for Chiang Mai over the last year from February 2007 to February 2008 and came up with the following:
- Chiang Mai – 49.85
I then worked out the daily average for March 2007 only and it worked out as the following:
- Chiang Mai – 161.7
When is the best time to visit Chiang Mai? The answer would depend on the state of your respiratory system – but I’d try to avoid March if possible!
If you’re interested in downloading the Excel spreadsheet with all the international data from the World Bank website – please click here.