Patna: Siwan registered the poorest air quality in Bihar over the past 24 hours, with an Air Quality Index (AQI) reading of 281, placing it firmly in the ‘poor’ category, according to data from the Central Pollution Control Board (CPCB).
In contrast, Patna recorded a moderate AQI of 126, while Aurangabad and Motihari followed closely with readings of 120 and 108 respectively. Buxar (97), Chhapra (77), and Gaya (78) fared slightly better, falling into the ‘satisfactory’ category.
The AQI scale, which ranges from zero to 500, classifies air quality into six categories: ‘good’ (0–50), ‘satisfactory’ (51–100), ‘moderate’ (101–200), ‘poor’ (201–300), ‘very poor’ (301–400), and ‘severe’ (401–500). According to the CPCB, prolonged exposure to ‘very poor’ air can trigger respiratory issues, while ‘severe’ levels pose health risks even to healthy individuals.
The AQI is calculated based on the concentration of eight pollutants: PM2.5, PM10, nitrogen oxides, sulphur dioxide, ozone, carbon monoxide, ammonia, and lead. In Patna, PM2.5—fine particulate matter smaller than 2.5 microns—has been identified as the primary contributor to air pollution, raising concerns over long-term public health impacts.
