The Geo-Informatics and Space Technology Development Agency (Gistda) reported at 8am that red levels of particulate matter 2.5 micrometres and less in diameter (PM2.5) ranged from 75.6 to 142.8 microgrammes per cubic metre (µg/m³) of air in Bangkok and 26 provinces. The air pollution was worse than Tuesday morning when red levels covered Bangkok and 19 provinces and the highest level of PM2.5 reached 116.4µg/m³.
The government-set safe threshold for PM2.5 is 37.5µg/m³ in Thailand. There are 76 provinces, reports the Bangkok Post.
The highest level yesterday morning, 142.8µg/m³, was recorded in Samut Songkhram, followed by 132.9 in Pathum Thani, 122.1 in Bangkok, 121 in Samut Sakhon, 117.8 in Nonthaburi, 107.2 in Sing Buri, 106.7 in Ratchaburi, 106.5 in Nakhon Pathom, 104.6 in Phetchaburi, 104.2 in Ayutthaya, 103.5 in Samut Prakan and 100.6 in Chachoengsao.
In descending order, two-digit red levels were detected in Chonburi, Ang Thong, Suphan Buri, Kanchanaburi, Lop Buri, Prachin Buri, Sa Kaeo, Nakhon Nayok, Prachuap Khiri Khan, Saraburi, Rayong, Uthai Thani, Chai Nat, Chanthaburi and Nakhon Sawan.
Orange levels (starting to harm health) of PM2.5 were recorded in 14 provinces, ranging from 38.8 to 71µg/m³. In descending order, they were Nakhon Ratchasima, Trat, Phitsanulok, Phetchabun, Phichit, Kamphaeng Phet, Chaiyaphum, Tak, Loei, Uttaradit, Buriram, Nong Bua Lam Phu, Sukhothai and Khon Kaen.
Eighteen provinces had moderate air quality with PM2.5 levels from 25.2 to 35.4µg/m³. In descending order, they were Nan, Phatthalung, Yala, Songkhla, Pattani, Trang, Narathiwat, Satun, Phuket, Krabi, Surin, Udon Thani, Phrae, Nakhon Si Thammarat, Nong Khai, Ubon Ratchathani, Phayao and Lampang.
Good air quality with PM2.5 levels between 15.1 and 24µg/m³ were in 14 provinces. In descending order, Lamphun, Si Sa Ket, Phangnga, Maha Sarakham, Surat Thani, Chumphon, Sakon Nakhon, Bueng Kan, Ranong, Kalasin, Chiang Rai, Roi Et, Chiang Mai and Mae Hong Son.
Four provinces – Yasothon, Mukdahan, Amnat Charoen and Nakhon Phanom – had very good air quality with PM2.5 levels of 11.1 to 13.3µg/m³.
The Pollution Control Department said thick smog would worsen from today to Monday next week in all regions except the South where air quality would remain good.