New Delhi, Nov 20 : The air quality at several monitoring stations again plunged to the 'severe' category on Monday morning. The Anand Vihar station was in the 'severe' category with PM 10 at 401 and PM 2.5 at 392, in a very 'poor' category, as per CPCB at 10 a.m. At the Bawana station, PM 2.5 reached 434 and PM 10 at 411, both in 'severe' category, while the CO reached 85, in 'satisfactory' levels and NO2 at 27 in the 'good' category. In Dwarka sector-8 station, the PM 2.5 reached 463 and PM 10 was at 478, both in the 'severe' category while NO2 reached 117 and CO was at 111 in 'moderate' levels. The air quality at the Indira Gandhi International Airport T3 area was 'severe' with PM 2.5 recorded at 436 and PM 10 at 366, in 'very poor' category, while the CO reached 122 under 'moderate' category and NO2 was at 49 in 'good' levels. At ITO station, the PM 2.5 plunged to 399 and PM 2.5 was at 371, both under 'very poor' category while the NO2 spiked to 244 in the 'poor' category and CO was at 101 in 'moderate' levels. The PM 2.5 at Jahangirpuri was recorded at 468 and Particulate Matter (PM) 10 reached 471 placing both under the 'severe' category. Here, the Carbon Monoxide (CO) was 100 in 'satisfactory' levels and Nitrogen dioxide (NO2) at 24, in the 'good' category The AQI between zero and 50 is considered 'good'; 51 and 100 'satisfactory'; 101 and 200 'moderate'; 201 and 300 'poor'; 301 and 400 'very poor'; and 401 and 500 'severe'. /IANS