Sarawak Haze Worsens as 11 Areas Record Unhealthy API, Serian Hits 189

KUALA LUMPUR, AUGUST 2026 — The number of areas in Sarawak recording unhealthy Air Pollutant Index (API) readings rose to 11 on Tuesday morning, up from nine locations a day earlier, as transboundary haze continued to affect air quality across the state.

According to data from Malaysia’s Air Pollutant Index Management System (APIMS), Serian recorded the highest API reading at 189, putting it close to the upper end of the unhealthy category.

Samarahan followed with an API reading of 170, while Kuching recorded 166. Other affected areas included Bintulu at 159, Samalaju at 156, Mukah and Sibu at 154 each, Sarikei at 153, and Sri Aman at 152.

Air quality in northern Sarawak was also affected, with Miri registering an API reading of 137, while the monitoring station at the Industrial Training Institute (ILP) Miri recorded 116. All 11 readings were within the unhealthy range.

The deterioration marks a further increase from August 10, when nine locations in Sarawak were reported to have unhealthy air quality. On that day, Serian also recorded the highest reading among the affected areas, highlighting the persistence of haze conditions in the state.

Understanding Malaysia’s API Levels

Malaysia classifies API readings between 0 and 50 as good, while readings from 51 to 100 are considered moderate. Levels between 101 and 200 are classified as unhealthy, while readings from 201 to 300 are considered very unhealthy. Any API reading above 300 is categorised as hazardous.

This means all 11 affected Sarawak locations remained within the unhealthy category on Tuesday morning, although none had crossed into the very unhealthy range at the time of the report.

Transboundary Haze Continues to Affect Sarawak

The worsening conditions come amid continued concerns over transboundary haze affecting Sarawak. Malaysia’s Department of Environment had previously confirmed deteriorating air quality in the state and intensified monitoring and enforcement measures, including activation of national action plans related to open burning and haze.

Earlier monitoring also indicated widespread hotspots in parts of the region, including Kalimantan and Sarawak, as authorities continued to monitor the movement and development of haze.

API readings can change throughout the day. Malaysia’s air pollution data is updated hourly through 68 air-quality monitoring stations nationwide, meaning conditions in affected areas may improve or deteriorate depending on weather patterns, wind direction and pollution levels.

The rise to 11 unhealthy locations underscores the continuing impact of the current haze episode on Sarawak, with Serian, Samarahan and Kuching among the areas recording the most elevated pollution levels as of the morning of August 11, 2026