Delhi Reports Cleanest September Air in Five Years

Delhi recorded its lowest monthly average Air Quality Index for September in the last five years, hitting 102 in 2026 according to the Ministry of Environment, Forest and Climate Change. This figure compares with 105 in September 2025, 105 in 2024, 108 in 2023, and 104 in 2022.

Air Quality Trends

The January through September period of 2026 also saw 194 days with a daily average AQI below 200, which falls into the moderate category, marking the highest count in five years. Delhi had 187 such days in 2025, 188 in 2024, 193 in 2023, and 146 in 2022. At the same time, poor to severe air quality days dropped to 79 during this period in 2026, down from 86 days in both 2025 and 2024, 80 days in 2023, and 127 days in 2022. The average PM2.5 concentration from January 1 to September 28 stood at 69 micrograms per cubic metre, matching the 2025 level and remaining lower than 81 in 2024, 73 in 2023, and 80 in 2022.

Context

The Commission for Air Quality Management is working with various stakeholders to control air pollution across the national capital region. Air quality in North India typically worsens during the winter months due to changing weather conditions and local emissions.