The air quality in the national capital remained in the 'very poor' category. Though the situation was “much better” compared to two days ago because of a change in the wind direction. According to Central Pollution Control Board (CPCB) data, Delhi witnessed six “severe” air days on the trot from November 4 to November 9. Besides air pollution, Delhiites witnessed a thick layer of toxic foam floating on the Yamuna river.