AIR POLLUTION in the North is expected to worsen following an end to the ban on outdoor burning in many provinces.
Both academics and authorities yesterday cautioned people in the North to be prepared for a new and final wave of hazardous haze, while the Regional Environment Office 1 (Chiang Mai) assured there were measures planned to limit burning in the open.
Somporn Chantara, a lecturer at the Faculty of Science, Chiang Mai University, said monitoring of information in recent years revealed that the number of hotspots in the nine northern provinces had increased sharply after the burning ban ended, worsening air pollution due to the accumulation of very fine particulate matter in the air.
Somporn said the smog season in the North could be longer and more severe because the summer storms during Songkran had not relieved the situation as hoped.
She said particulate matter smaller than 2.5 microns (PM2.5) in the air was still high, hence people in the North were still unsafe and they must closely monitor the air pollution level, especially PM2.5, during this period.
“A study of particulate matter emission from outdoor burning shows that more than 70 per cent of particulate matter from open burning was PM2.5, so I would like the authorities to use the PM2.5 level to warn the people, as the PM10 level alone does not always represent the actual air quality,” she said.
The Director of Regional Environment Office 1 (Chiang Mai), Rapeesak Malairungsakul, also said the rapid increase in the number of hotspots and the worsening haze had become a regular problem and was yet to be solved as many people burned their fields at the same time once the ban expired.
“In order to mitigate this problem some provinces, such as Chiang Mai, have issued local regulation to control burning. Even after the ban period is over, anyone who wants to burn during seven days after the ban must seek permission from local authorities,” Rapeesak said.
“This measure is to prevent everyone from burning at the same time and worsening the air pollution.”
However, he said Thailand’s hotspots were not the only cause of smog in many northern provinces – there were even more hotspots in neighbouring countries and the wind carried the smog into Thailand.
The burning ban was another smog-prevention measure, imposed by local authorities in regularly affected areas in nine northern provinces.
During the 60 days of the burning ban, whose timing varied for each province, no outdoor burning activities were allowed and those who violate the ban faced punishment.
The reason for imposing the ban was because at this time of the year the farmers normally burn their farmland to prepare for the next |season and the smoke from open burning is a major factor in air pollution in the mountainous northern region.
As of now, the burning ban has already expired in six provinces – in Tak and Lampang since last Tuesday, in Nan and Phayao since Sunday, and in Chiang Rai and Phrae since yesterday.
The ban ends on Friday in Lamphun and Chiang Mai, and on April 30 in Mae Hong Son.