Chiang Mai on Saturday remained the most air-polluted city in the world for the second consecutive day, according to the AirVisual.com website.
AirVisual reported at 9.13am that the air quality index (AQI) of Chiang Mai on Saturday stood at 385, much higher than the 100 AQI safety standard.
The northern capital has been covered with white smog for almost two weeks, prompting Chiang Mai residents to wear N95 air-filter marks outdoors.
The Chiang Mai University, the Rajamangala University of Technology Lanna and Chiang Mai provincial administration confirmed that the air quality in the city remained critical.
The three agencies had 86 stations to measure air quality of the northern capital and found that all stations recorded brown and purple zones, meaning the air quality remained hazardous to health.
They found the worst air quality was in Mae Taeng district with a PM2.5 level of 443 micrograms per cubic metre (mcg). PM2.5 means airborne particulates 2.5 microns or less in diameter.
Doi Saket district was found to have the least PM.5 level or 204mcg, which was still hazardous to health.
The website of the Geo-Informatics and Space Technology Development Agency reported Saturday that its VIIRS satellite spotted 586 hotspots from forest burning in the North.
It reported that 162 hotspots were detected in Mae Hong Son, 91 in Chiang Rai, 69 in Chiang Mai, 79 in Nan, 55 in Prae, 55 in Phayao, 52 in Lampang, 14 in Tak and 9 in Lamphun.
The high level of haze in Chiang Rai reportedly stemmed from the many forest fires, both in the province and from nearby areas.