New Delhi, Jan 24 : There seems to be no relief from deteriorating air quality despite the Commission for Air Quality Management's (CAQM) Graded Response Action Plan (GRAP) stage-II in force as the air quality index (AQI) dipped to 'severe' levels at several stations on Wednesday morning. The experts attribute the current weather conditions being responsible for the bad air quality and turning the national capital into a 'gas chamber'. The Anand Vihar station was in the 'severe' category at 8 a.m. with PM 2.5 at 411 and PM 10 at 385 or 'very poor', while the NO plunged to 87, and CO reached 66, both in 'satisfactory' category, as per the Central Pollution Control Board (CPCB). However, at 10 a.m. the PM 2.5 slightly improved at Anand Vihar station and reached 385 and PM 10 at 363, both in the 'very poor' category. Dwarka Sector 8 witnessed PM2.5 levels at 437, and PM10 was at 403, both falling under the 'severe' category while CO was at 96, in satisfactory levels. However, the air quality at the Indira Gandhi International Airport T3 area was 'very poor' with PM 2.5 recorded at 359 and PM 10 at 358, while the CO plummeted at 68, under 'satisfactory' category. At Okhla Phase-II station, the PM 2.5 plunged to 411 and PM 10 was at 403, both under 'severe' category while the NO2 spiked to 78, and CO was at 62, though both in satisfactory levels. Notably, 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