Residents of 44 provinces enjoyed good to very good air quality on Monday morning, while 12 of the 76 provinces had orange (starting to affect health) levels of PM2.5, according to Gistda.
The Geo-Informatics and Space Technology Development Agency (Gistda) reported at 8am that the whole country was free of red levels (hazardous-to-health) of particulate matter 2.5 micrometres and less in diameter (PM2.5).
The orange levels of PM2.5 over the previous 24 hours ranged from 39 to 66.1µg/m³ in 12 provinces. Seven of them were northern provinces - Chiang Mai, Lampang, Lamphun, Nan, Phayao, Phrae and Sukhothai. The five others were Nakhon Pathom, Phetchaburi, Ratchaburi, Samut Songkhram and Trat.
The government-set safe threshold is 37.5µg/m³.
Bangkok was among 21 provinces with moderate air quality, recording yellow levels of PM2.5 ranging from 25.4 to 37.2µg/m³.
Other provinces with moderate air quality were, in descending order of PM2.5 levels, Tak, Uttaradit, Rayong, Samut Sakhon, Yala, Narathiwat, Prachuap Khiri Khan, Pattani, Chon Buri, Samut Prakan, Mae Hong Son, Kanchanaburi, Nonthaburi, Chachoengsao, Kamphaeng Phet, Phitsanulok, Pathum Thani, Nakhon Phanom, Chiang Rai and Chanthaburi.
Seventeen provinces had good air quality, reporting green levels of PM2.5 ranging from 15.1 to 24.9µg/m³.
They were, in descending order, Phuket, Chumphon, Trang, Phangnga, Ranong, Loei, Prachin Buri, Phetchabun, Nakhon Si Thammarat, Phichit, Uthai Thani, Krabi, Surat Thani, Nakhon Sawan, Suphan Buri, Yasothon and Sa Kaeo.
As many as 27 provinces had very good air quality represented by blue levels of PM2.5 ranging from 7.7 to 14.2µg/m³. Ang Thong recorded the lowest level.
Other provinces with very good air were Amnat Charoen, Ayutthaya, Bueng Kan, Buri Ram, Chainat, Chaiyaphum, Kalasin, Khon Kaen, Lop Buri, Maha Sarakham, Mukdahan, Nakhon Nayok, Nakhon Ratchasima, Nong Bua Lam Phu, Nong Khai, Phatthalung, Roi Et, Sakon Nakhon, Saraburi, Satun, Sing Buri, Si Sa Ket, Songkhla, Surin, Udon Thani and Ubon Ratchathani.
The Meteorological Department said a powerful high pressure system from China brought strong winds and also reduced temperatures by 4-6°C in the Northeast and 1-3°C in the Central Plain and the East.
