Delhi's Air Pollution Crisis, What's Being Done?

After the Supreme Court intervened over Delhi pollution crisis, schools have been shut and all construction activities have been halted. These measures have already been mandated in the Supreme Court-approved Graded Response Action Plan (Grap). But why do they take so long to be enforced? Also, what steps have we taken to curb the annual winter pollution. We speak to Anumita Roy Chowdhury, executive director, research and advocacy, centre for science and environment (CSE) and Dr Vijay Hadda, assistant professor, department of pulmonary medicine, AIIMS.