Riau's Air Quality at Night (9/1) is the Worst in Indonesia

The air quality in Riau tonight is the worst in Indonesia. Based on the Air Pollutant Standard Index (ISPU) page of the Ministry of Environment and Forestry (KLHK) on Friday (Jan 9, 2026) at 6:00 PM WIB, it was revealed that Riau's air quality index was 101.

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

ISPU calculation is based on the measurement results of seven air pollutant parameters, namely PM10, PM2.5, NO2, SO2, CO, O3, and HC. Air pollutant parameter measurements 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 means moderate air quality, and 101-200 indicates unhealthy air quality that is detrimental to humans, animals, and plants.

Next, 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 over 300 can seriously harm health and requires quick handling.

Below Riau, Banten ranks second worst in Indonesia with an air quality index of 95. Then, in third place is South Sumatra with an air quality index of 91.

This means that no region has hazardous air quality.

Here is a list of the 10 provinces with the worst air quality index in Indonesia on Friday, January 9, 2026, at 6:00 PM WIB.

1. Riau: 101

2. Banten: 95

3. Sumatera Selatan: 91

4. Aceh: 88

5. Suamtera Utara: 87

6. Sumatera Barat: 86

7. Lampung: 74

8. Jawa Tengah: 70

9. Kalimantan Tengah: 68

10. Kalimantan Selatan: 67

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