A provincial-level emergency response system for heavy pollution days has also been set up, under a plan released by the Hebei provincial government in August.

The plan says if the provincial meteorological observatory predicts an air quality index reading of above 200, which indicates a heavy pollution day, for the following 24 to 72 hours, the observatory should hold a meeting with the monitoring station to acquire accurate details of the pollution, such as the time range, the geographical areas and the levels.

All information should be reported to the provincial government before noon and later be released to the public.

New emission standards issued

The Environmental Protection Ministry issued phase 5 of emission standards for light vehicles, both gasoline and diesel, on Tuesday.

The new standards will help reduce emissions of 90,000 metric tons of nitrogen oxide and 20,000 tons of particles in five years after it is implemented.

China has been the world's top automobile producer and seller for four consecutive years. During that period, the number of motor vehicles has grown at 12 percent every year, reaching 80 million at the end of 2011.

Airborne pollutants emitted by automobiles are also increasing, accounting for more than 20 percent of the total amount of fine particles in the air, according to the ministry.

The phase 5 standard, issued eight years after phase 4, sets a stricter emission limit for nitrogen oxide, a reduction of about 25 to 28 percent. It also requires the emissions of particles to drop by 82 percent.

Once implemented, phase 5 of the gasoline and diesel standards will set sulfur content lower than 10 micrograms per gram of gasoline, cutting about 300,000 tons of nitrogen oxide and 30,000 tons of particles annually, according to the ministry.

Phase 5 will be implemented on Jan 1, 2018, due to the lack of fuel that is fit for automobiles under the new standards.