North Sumatra's Air Quality on Saturday Night (12/13) Worst in Indonesia

Air quality in North Sumatra tonight is the worst in Indonesia. Based on the Air Pollution Standard Index (ISPU) page of the Ministry of Environment and Forestry (KLHK) on Saturday (12/13/2025) at 6:00 PM WIB, it was revealed that the air quality index in North Sumatra was 261.

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

ISPU calculations are 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.

(Read: Chad Becomes Country with Worst Air Quality in the World 2024)

Based on Ministry of Environment and Forestry Regulation No. 14 of 2020 concerning the Air Pollution 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 harmful to humans, animals, and plants.

Furthermore, very unhealthy air quality in the 201-300 range can increase health risks for sensitive groups. Meanwhile, hazardous air quality in the range above 300 can seriously harm health and requires prompt handling.

Below North Sumatra, Riau ranks second worst in Indonesia with an air quality index of 99. Then, in third place is Banten with an air quality index of 95.

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 Saturday, December 13, 2025, at 6:00 PM WIB.

1. North Sumatra: 261

2. Riau: 99

3. Banten: 95

4. South Sumatra: 90

5. Central Kalimantan: 89

6. North Sumatra: 88

7. West Sumatra: 87

8. West Java: 83

9. Lampung: 74

10. Central Java: 70

(Read: Chad Becomes Country with Worst Air Quality in the World 2024)