Air quality across Delhi yet again dipped to 'severe' category with the AQI hitting alarming levels at several places on Wednesday. The Anand Vihar station was in the 'severe' category with PM 2.5 at 500 and PM 10 at 476, while the Carbon monoxide (CO) was at 102, under 'moderate' category, and the NO2 at 53, in satisfactory levels, as per CPCB at 9 a.m.At the Bawana station, PM 2.5 reached 500 and PM 10 at 435, while the CO reached 95, in 'satisfactory' levels and NO2 at 21, in the 'good' category.