Delhi's Air Quality Improves, Supreme Court Allows Withdrawal Of GRAP-4

The Supreme Court on Thursday permitted the relaxation of the GRAP IV stage after the Commission for Air Quality Management (CAQM) said that there is improvement in the air quality and stated that the measures under GRAP IV are no longer required.

The GRAP (Graded Response Action Plan) measures are in place to tackle air pollution in Delhi. The top court was hearing a matter over measures to curb air pollution in Delhi-NCR areas.

The overall Air Quality Index (AQI) recorded in Delhi today was 161, categorised as 'moderate' as of 8 am, according to the data of the Central Pollution Control Board (CPCB), after the city faced persistent air pollution since last one month.

An AQI between zero and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'.

Delhi's AQI was reeling in 'very severe', 'severe', 'very poor' and 'poor' categories post-Diwali. Residents in the region complained of breathing difficulties and several other medical problems.

Increasing AQI in the city led to the implementation of Graded Response Action Plan (GRAP)-IV measures to curb air pollution. Stage IV enforces a ban on the operation of Delhi-registered BS-IV and below diesel-operated medium goods vehicles (MGVs) and heavy goods vehicles (HGVs), except for essential services.

Stubble burning in Punjab and Haryana is among the main reasons for air pollution in Delhi-NCR and several steps are being taken to encourage farmers to use paddy residue for animal feed and industrial purposes, a top Union environment ministry official told parliamentarians on Wednesday.

On Tuesday, the National Green Tribunal or NGT sought a response from the Centre on the "persistent air pollution crisis" in the national capital.

The NGT was hearing the matter where it had taken suo motu (on its own) cognisance of a media report based on a study about the reasons for air pollution being emissions from thermal plants and the prevailing weather conditions.

"As per the article, a recent study by the Centre for Research on Energy and Clean Air (CREA) has revealed that thermal power plants in the region are responsible for emitting 16 times more air pollution than the pollution caused by stubble burning," a bench of NGT Chairperson Justice Prakash Shrivastava said in an order passed on November 27. 

The green body also said that as per the article, weather conditions in Delhi were exacerbating the pollution crisis and calm winds and dropping temperatures, also known as cold air traps, had hindered the dispersal of pollutants by trapping dust, smoke, and other harmful particles in the air.