Residents of some of China’s most polluted cities have been ordered to switch from coal to natural gas heating by the end of this month to meet the country’s air quality targets. The 1.18 million households in 11 cities in three central provinces must make the switch by the end of October, the Ministry of Ecology and Environment (MEE) said on Monday, as part of the country’s anti-air pollution campaign. The 11 cities are located in the Fenwei Plain which is comprised of the provinces of Shanxi and Shaanxi, two of China’s biggest coal producing regions, as well as Henan. The area was included by Beijing as a “key battlefield” in the war against air pollution in July on top of 28 other cities in northern China. Air pollution in the Fenwei Plain is a concern. The city of Linfen in Shanxi, which has been called the most polluted city on Earth, was identified as having the worst air quality among 169 cities it monitors in the first nine months of this year, the MEE said. Air pollution is killing 1 million people and costing Chinese economy 267 billion yuan a year Moving from coal to gas is supposed to reduce the amount of pollution from particulate matter measuring 2.5 microns (PM2.5), pollution that is considered the most hazardous since it can lodge deep in the lungs. The Fenwei Plain region must cut its average concentration of PM2.5 by 4 per cent between October and March next year from same period last year, the MEE said. Local governments will need to promote consolidation in the coke and steel industry to eliminate small and outdated capacity and improve the emission standards of the sectors. The MEE also asked the region to accelerate switching from road to railroad transportation by accelerating construction of rail lines connecting ports with coal mines, utilities, steel mills and coke plants. Heavy industry in the Fenwei Plain will need to implement production restrictions during the heating season, typically from mid-November until mid-March, or shut down if they fail to meet certain emission standards, the MEE said. Detailed output cutting plans will be set by individual cities by the end of October, it said. The households switched to gas in the Fenwei plain are in addition to the 3.62 million that need to be switched in the 28 other northern Chinese cities, the MEE said.