A decision on the reopening of schools and lifting of construction ban will be taken on or before December 17, and will be based on the impact of relaxations that are already being made for industrial units, the air quality commission told the Supreme Court today ahead of a hearing tomorrow. The court had last week noted that the air quality in the national capital had started improving, and had directed the pollution panel to take a decision on relaxing restrictions imposed by the court on sources of pollution - including industries, constructions, and factories - in the national capital.