The Supreme Court on Friday will hear a plea by a group of traders who have asked for a modification of the court’s October 9 order that banned the sale of firecrackers in Delhi and the National Capital Region until November 1. The court had said it wanted to use the ban to study the difference in air quality in a region prone to high levels pollution.

On October 11, the traders moved court saying they had renewed their licences and have already bought firecrackers to sell during Diwali. They said they bought their stock in September after a temporary relaxation of the restriction imposed in 2016, when the bench said a complete ban would be “extreme”.

On Monday, a three-judge bench of the Supreme Court restored its November 2016 order, banning the sale of crackers in NCR, and suspended its September order, which allowed limited sale, but banned imports from other states.

While crackers are not the only contributors to the Capital’s pollution problem, the ambient air quality had deteriorated by more than three times the average levels the morning after Diwali in 2016.