A layer of smog enveloped Delhi-NCR on Saturday morning, with the Air Quality Index (AQI) reflecting a ‘poor’ rating just two days after Diwali, despite a govt ban on firecrackers. According to the Central Pollution Control Board (CPCB), Delhi’s average AQI was 294 at 7:30 A.M., with several areas, including Anand Vihar and IGI Airport, exceeding 300, indicating ‘very poor’ air quality.