Delhi imposes strict GRAP-3 anti-pollution curbs as air quality turns ‘severe’

The national capital’s air quality slipped into the ‘severe’ category on Saturday morning after wind speeds fell under the influence of a western disturbance, prompting the Commission for Air Quality Management (CAQM) in the National Capital Region (NCR) and adjoining areas to invoke Stage III of the Graded Response Action Plan (GRAP).

“Keeping in view the prevailing trend of air quality and in an effort to prevent further deterioration of air quality in the region, the CAQM GRAP Sub-Committee today has taken the call to invoke all actions as envisaged under Stage III of the extant GRAP — ‘Severe’ air quality (Delhi AQI ranging between 401–450), with immediate effect, in the entire NCR. This is in addition to the actions under Stages I and II of the extant GRAP already in force in the NCR,” CAQM said.

The Air Quality Index (AQI) was recorded at 401 (severe) at 11 am on Saturday, according to data from the Central Pollution Control Board (CPCB). The 24-hour average AQI was recorded at 349 (very poor) at 4 pm a day earlier.

“The wind speed has been very low since Friday, leading to a spike in pollution levels. Due to the western disturbance, the AQI might remain in this range on Sunday as well. Wind speed might pick up from Monday again, bringing some respite,” Skymet vice-president Mahesh Palawat said.

Forecasts by the Air Quality Early Warning System for Delhi (AQEWS) suggest that air quality is expected to remain in the severe category on Sunday and improve to the very poor category on Monday.

“The air quality is likely to be in the severe category on Sunday. The air quality is likely to be in the very poor category on Monday. The outlook for the subsequent six days is that the air quality is likely to be in the very poor category,” the AQEWS bulletin said.

CAQM officials said that NCR pollution control boards and other concerned agencies have also been asked to escalate preventive measures to prevent further deterioration of air quality in the region.

GRAP has four stages, which are invoked as precautionary measures to battle air pollution. Stage-1 of GRAP is generally invoked when the AQI crosses 200. Stage-2 (very poor) measures are invoked when the AQI crosses 300; stage-3 (severe) measures have been set at 400 (severe) and stage 4 at 450.

GRAP’s stage 3 brings with it a ban on BS-3 petrol and BS-4 diesel four-wheelers in Delhi, Gurugram, Faridabad, Ghaziabad, and Gautam Budh Nagar, blanket curbs on private construction and demolitions, and restrictions on the use of stone crushers, mining and associated activities.

Schools up to Class 5 in Delhi and its neighbouring districts will also have to shift to “hybrid” lessons under it.