West Sumatra's Night Air Pollution (Oct 27) Worst in Indonesia

Tonight, air quality in West Sumatra is the worst in Indonesia. Based on the Air Pollutant Standard Index (ISPU) page of the Ministry of Environment and Forestry (KLHK) on Monday (27/10/2025) at 6:00 PM WIB, it was revealed that West Sumatra's air quality index was 97.

According to the Directorate of Air Pollution Control KLHK, ISPU is a unitless number used to describe the ambient air quality conditions in a specific location and is based on its impact on human health, aesthetic value, and other living things.

ISPU calculation is based on the measurement results of seven air pollutant parameters: PM10, PM2.5, NO2, SO2, CO, O3, and HC. Measurements of air pollutant parameters are spread across 72 stations in various regions.

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Based on Ministry of Environment and Forestry Regulation No. 14 of 2020 concerning the Air Pollutant Standard Index, an ISPU in the range of 0-50 indicates good air quality, 51-100 indicates moderate air quality, and 101-200 indicates unhealthy air quality that is detrimental to humans, animals, and plants.

Furthermore, very unhealthy air quality in the range of 201-300 can increase health risks for sensitive groups. Meanwhile, hazardous air quality in the range of more than 300 can seriously harm health and requires rapid intervention.

Below West Sumatra, Banten ranks second worst in Indonesia with an air quality index of 95. Then, in third place is East Java with an air quality index of 93.

This means no region has hazardous air quality.

Here is a list of the 10 provinces with the worst air quality index in Indonesia on Monday, October 27, 2025, at 6:00 PM WIB.

1. West Sumatra: 97

2. Banten: 95

3. East Java: 93

4. Jambi: 89

5. Aceh: 84

6. West Java: 82

7. Riau: 81

8. Central Java: 75

9. Central Kalimantan: 72

10. Riau Islands: 67

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