Six areas in Sarawak recorded very unhealthy Air Pollutant Index (API) readings as of 4pm on September 5, 2026, with Kuching reporting the highest levels between 264 and 275. The affected areas included Kuching, Serian District Police Headquarters, Sri Aman, Samarahan, Bintulu, and Samalaju, with API values mostly between 207 and 275 [1, 2, 3, 4].
Serian reached a hazardous API peak of 287 at 1pm on September 5, but this dropped to 207 the following morning after rain [5, 6]. The Air Pollutant Index scale categorizes 201-300 as very unhealthy and values above 300 as hazardous [1, 2, 3, 7, 5, 8].
On the morning of September 6 (8-10am), Kuching and Sri Aman recorded very unhealthy API readings ranging from 215 to 235, with Kuching levels around 223 to 235. By the afternoon (4pm), Sri Aman was the only area maintaining a very unhealthy reading of 216, while Kuching and others had decreased to unhealthy but below the very unhealthy range [7, 5, 8, 9, 10, 11].
Sarawak remained the worst-affected state with multiple other areas such as Miri, Mukah, Sibu, Sarikei, Limbang, Kapit, and Samalaju reporting unhealthy to very unhealthy air quality levels [1, 2, 3, 7, 8, 9, 11]. Nationwide, 25 to 35 areas recorded unhealthy API readings during September 5 and 6, while around 26 to 27 areas had moderate levels and 8 to 10 areas recorded good air quality, with no hazardous readings reported on September 6 [1, 2, 3, 7, 8, 9, 11].
Authorities in Sarawak are actively monitoring bush and peat fires near Sibu and Samarahan that contribute to the haze. Firefighting efforts are ongoing, with partial containment reported. Deputy Director (Development) of the Malaysia Environment Department Haji Azuly said, "We are especially monitoring bush and peat fires near Sibujaya Barat and Sungai Nai areas in Sarawak as hot dry weather may worsen the fire conditions and lead to smoke and air pollution" [10].
Fine particulate matter is a key pollutant driving the unhealthy and very unhealthy air quality readings in the region [3]. Under national guidelines, schools are required to close when the API exceeds 200, and outdoor activities must stop above 100. Artificial rainmaking can be considered if the API remains above 150 for more than 24 hours and the weather allows [10].
Higher Education Minister Datuk Seri Dr Zambry Abd Kadir stated, "We have informed higher education institutions, universities, polytechnics and also community colleges to constantly monitor, especially in the areas of Sabah and Sarawak which are more seriously affected" [6]. Universities and colleges in the region have been instructed to switch to online classes if needed.
The worsening haze also affected events outside Sarawak. The Selangor 2026 Para Sukma postponed four para sports events on September 6 due to unhealthy API readings of 169 in Shah Alam and Klang. Deputy chairman of the organising committee Mohd Najwan Halimi said, "The API readings in Shah Alam and Klang as of noon today showed an unhealthy level of 169. This has forced the Selangor Para Sukma organisers to postpone four sports" [12].
