According to official data, Delhi's 24-hour average Air Quality Index (AQI) at 4 PM was 345, which falls under the 'Very Poor' category, compared to 326 recorded on Sunday.

During "very poor" air quality, residents may face breathing discomfort, while "severe" levels can impact even healthy individuals and worsen existing conditions

The air quality in most areas in Delhi plummeted into either ‘very poor’ or ‘severe’ categories after Diwali fireworks. Anti-pollution measures are likely to be scaled up in view of the worsening pollution in the national capital.

The Air Quality Index (AQI) of Delhi and its surrounding areas increased drastically to 'very poor' category, a day after Diwali. The national capital territory (NCT) woke up to thick and heavy layer of smog.

Majority metropolitan cities in India showed a significant decline in air quality as parts of the country woke up to smog a day after Diwali was celebrated. Among all metro cities, Delhi recorded the highest air quality index (AQI),

The air quality in many areas was in the 'severe' category in Delhi-NCR. The AQI between 0 and 50 is categorised as 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor',

Delhi air quality witnessed a sharp decline on Monday as the national capital marked Diwali 2025 amid a ban on bursting fire crackers.