The central government's air quality monitoring panel on Tuesday revoked the pollution control measures under stage 4 of the Graded Response Action Plan as the air pollution levels showed a declining trend in the national capital.
However, the restrictions under stages 1, 2 and 3 would remain in force to prevent any deterioration of air quality, the Commission for Air Quality Management (CAQM) announced.
The 24-hour average Air Quality Index (AQI) stood at 369 at 4 pm on Tuesday. The AQI had touched 401 (Severe) on December 16.
"Actions under Stage I, II, and III of the revised GRAP shall remain invoked and be implemented, monitored, and reviewed by all the agencies concerned in the entire NCR to ensure that the AQI levels do not slip further," the CAQM said.
The air quality was improved due to favourable meteorological conditions, including improved wind speed, according to forecasts from the India Meteorological Department and the Indian Institute of Tropical Meteorology.
Under GRAP-4 measures, all construction activities in the national capital had been banned while entry of non-essential polluting trucks into Delhi had also been stopped. Classes, except those for 10 and 12, were shifted to hybrid mode.
Under Stage-3, classes up to 5 are required to shift to hybrid mode. Parents and students have the option to choose online education, wherever available. Stage-3 also bans non-essential diesel-operated medium goods vehicles of BS-IV or older standards in Delhi.
"Keeping in view the winter season, when weather conditions may not always be favourable, and to ensure that AQI levels do not slip further, citizens are requested to strictly adhere to the Citizen Charter under GRAP-III," the air quality panel said in its circular.