Delhi residents can breathe a sigh of relief as the Commission for Air Quality Management (CAQM) has lifted the restrictions imposed under Stage IV of the Graded Response Action Plan (GRAP) with immediate effect. This decision comes as the air quality in the National Capital Region (NCR) has improved from "severe" to "very poor". While GRAP-IV curbs are lifted, measures under Stages I, II, and III will remain in place.
The CAQM's decision is based on the improved Air Quality Index (AQI), which has moved from the "severe" category to the "very poor" category. On Wednesday morning, Delhi's AQI stood at 336, a notable decrease from Tuesday's reading of 415. Data from the Central Pollution Control Board (CPCB) revealed that out of 40 air quality monitoring stations in Delhi, 36 recorded AQIs in the "very poor" category. As of Wednesday afternoon, the real-time AQI in Delhi was reported as "poor". One source reported an AQI of 127 (US AQI), while another indicated 145. These variations could be due to different monitoring locations and calculation methodologies. Current readings show major air pollutants as PM2.5 at 47µg/m³, PM10 at 67µg/m³, CO at 243ppb, SO2 at 6ppb, NO2 at 25ppb, and O3 at 31ppb.
GRAP is a set of emergency measures implemented to control and reduce air pollution levels in Delhi-NCR. It was formulated under the direction of the Supreme Court of India and came into effect in 2017. The plan categorizes pollution control measures into four stages based on AQI levels. Stage I is activated when the AQI falls between 201 and 300, indicating "poor" air quality, and involves basic pollution control measures such as road dust management and enforcing vehicle Pollution Under Control (PUC) norms. Stage II is implemented when the AQI reaches 301-400, signifying "very poor" air quality, and includes stricter actions like limiting diesel generator use and controlling operations in pollution hotspots. Stage III is enforced when the AQI hits 401-450, indicating "severe" air quality, and imposes restrictions on specific vehicles and construction activities, and may allow for remote schooling. Stage IV, the most severe, is activated when the AQI exceeds 450, enforcing bans on the entry of heavy vehicles, closures of schools, and shutdowns of non-essential industries.
With the lifting of GRAP-IV restrictions, the focus shifts to the continued implementation of Stages I, II, and III. These stages involve a range of measures aimed at curbing pollution from various sources. These include dust suppression at construction sites, promotion of carpooling and public transport, bans on waste burning, and monitoring of industrial emissions. Restrictions include intensified patrolling, strict action against open burning of garbage and biomass, and ban on diesel generators except for emergencies.
While the lifting of GRAP-IV provides some respite, the persistence of "very poor" air quality underscores the ongoing challenge of combating pollution in Delhi. Air pollution in Delhi-NCR during winter is influenced by local and regional factors, including emissions from vehicles, construction, industrial activity, and agricultural burning, as well as meteorological conditions that trap pollutants. The Graded Response Action Plan (GRAP) remains a critical tool in addressing Delhi-NCR's persistent air pollution crisis.
