Earlier in the day, the state government decided to reopen primary classes from November 9 and revoke the order that asked 50 per cent of its staff to work from home as the air quality in the naional capital improved. "BS-III petrol and BS-IV diesel four-wheelers in Delhi will remain banned under Stage 3 of the Graded Response Action Plan (GRAP)," Delhi Environment Minister Gopal Rai said at a press conference.