The Environment Pollution (Prevention and Control) Authority (EPCA) on Priority measures to reduce air pollution and protect public health, in its February 2014 report came to be treated as a petition by the Forest Bench headed by Justice AK Patnaik, who asked the States and Centre to respond to the report by March 10. Amicus curiae Harish Salve who presented the report informed the Court that this winter Delhi’s air pollution levels exhibited shocking figures. Through the winters, asthma and cardiac patients remained at high risks as PM levels stood at 2.5 with tiny particles entering deep inside the lungs. During high smog, it was 8 to 10 times higher than the standards.

Annual average particulate matter (PM) levels were reduced by about 16 per cent between 2002 and 2007 but marked an increase by 75 per cent after 2007. The nitrogen dioxide levels also showed a 30 per cent increase over 2002. During the same decade (2002 to 2012), vehicle numbers increased by as much as 97 per cent, the report said.

The report recommended favourable taxing policy for CNG over diesel. In 2002-03, CNG was cheaper than diesel by about 46.71 per cent. By 2009, the difference increased to more than 50 per cent as diesel prices increased. But in December 2013, the price differential fell to 7.35 per cent, that saw a sharp increase in sale of private diesel cars. The report sought urgent introduction of Bharat Standard IV emission norms and encourage public transport by imposing heavy tax and parking fare on cars.