The Centre on Saturday ordered the revocation of a ban on construction work related to linear public projects in Delhi-NCR and the entry of polluting trucks and commercial four-wheelers into the national capital following an improvement air quality in the region due to favourable wind speed and direction.

These measures constitute the final stage, Stage IV, of the Centre's air pollution control plan, which is activated at least three days before the Air Quality Index (AQI) surpasses the 450-mark in the capital.

The Commission for Air Quality Management in National Capital Region and Adjoining Areas (CAQM), a statutory body responsible for formulating strategies to combat pollution in the region, asked Delhi and NCR states to revoke all emergency measures, which allow only CNG, electric and BS VI-compliant vehicles from other states to enter Delhi, with exemptions granted to those involved in essential services.

All medium and heavy goods vehicles not engaged in essential services were also banned in the capital under Stage IV of GRAP, according to the latest CAQM order.

The air quality forecasts by the India Meteorological Department/Indian Institute of Tropical Meteorology do not indicate any steep degradation in the overall air quality of Delhi-NCR in the coming days, the CAQM said.

The city's 24-hour average AQI, recorded at 4 pm every day, improved from 405 on Friday to 319 on Saturday.

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