A stringent ban on the use of coal and other unapproved fuels in industries and commercial establishments came into force in Delhi-NCR on Sunday, with officials saying defaulting units will be closed down without any warning.

However, the use of low-sulphur coal in thermal power plants is allowed, the central government's Commission for Air Quality Management said (CAQM).

The ban is part of a comprehensive policy released by the CAQM in July last year. The policy lists sector-wise action plans to curb air pollution in Delhi-NCR in the next five years.

Authorities have been directed to close down industries and commercial establishments using unapproved fuels, including coal, without giving them any show-cause notice.

A heavy fine will be levied on the defaulting units, a CAQM official said.

He said the panel had announced the ban six months ago, giving enough time to all industries to shift to cleaner fuels.

The use of low-sulphur coal is also allowed in captive thermal power plants, the official clarified, saying "it could be used wherever the primary purpose is power generation".

Firewood and biomass briquettes can be used for religious purposes and cremation, wood or bamboo charcoal can be used for tandoors and grills of hotels, restaurants, banquet halls (with emission control system) and open eateries or dhabas.

The use of wood charcoal for cloth ironing is allowed, the CAQM had said earlier.

The commission had in June issued directions to ban the use of coal in industrial, domestic and other miscellaneous applications in the entire Delhi-NCR from January 1, 2023.

Around 1.7 million tonnes of coal is used annually in industrial applications in the National Capital Region (NCR), with about 1.4 million tonnes being consumed in six major industrial districts alone. In a bid to reduce vehicular pollution, the Centre's air quality panel has also directed Uttar Pradesh, Rajasthan and Haryana to register only CNG and electric autos from January 1 (Sunday) and complete the phase out of the diesel ones in the NCR by the end of 2026.

The objective is that only CNG and e-autos ply in the NCR from January 1, 2027.

The NCR covers Delhi, 14 districts of Haryana, eight districts of Uttar Pradesh and two districts of Rajasthan.

According to the CAQM's directions, diesel autos in Ghaziabad, Gautam Budh Nagar, Faridabad and Gurugram will have to be moved out of service by the end of 2024.

Sonepat, Rohtak, Jhajjar and Baghpat will have to do so by December 31, 2025. The deadline for the rest of the areas in the NCR is the end of 2026.

Delhi had launched a programme in 1998 to convert its fleet of diesel auto rickshaws into CNG ones. No diesel-run auto is registered in Delhi at present.

The Delhi Transport Department had launched a scheme in October last year for registration of 4,261 e-autos.

Vehicles account for 40 percent of PM 2.5 emissions in the capital.

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