North Sumatra's Air Quality at Night (15/12) is the Worst in Indonesia

North Sumatra's air quality tonight is the worst in Indonesia. Based on the Air Pollutant Standard Index (ISPU) page of the Ministry of Environment and Forestry (KLHK) on Monday (15/12/2025) at 18.00 WIB, it was revealed that North Sumatra's air quality index was 1092.

According to the KLHK Directorate of Air Pollution Control, 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 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.

(Read: There Were Nearly 300 Natural Disasters Until Mid-February 2024)

Based on KLHK 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 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 above 300 can seriously harm health and requires immediate action.

Below North Sumatra, South Sumatra ranks as the second worst in Indonesia with an air quality index of 97. Then, in third place is Banten with an air quality index of 95.

This means North Sumatra has hazardous air quality.

Here is the list of the 10 provinces with the worst air quality index in Indonesia on Monday, December 15, 2025, at 18.00 WIB.

1. North Sumatra: 1092

2. South Sumatra: 97

3. Banten: 95

4. Jambi: 93

5. Central Kalimantan: 89

6. Riau: 88

7. West Sumatra: 87

8. North Sumatra: 85

9. East Kalimantan: 74

10. Central Java: 70

(Read: There Were Nearly 300 Natural Disasters Until Mid-February 2024)