Each of the coal-fueled furnace will be fined up to 100,000 yuan (about 12,092 US dollars) if they fail to fulfill the requirement, deputy director Zheng Jiang of local environmental protection bureau was quoted as saying by Thursday's Beijing Youth Daily.

Calling such furnace whose annual coal consumption is more than 20 tons "a major culprit of Beijing's air pollution", Zheng said these "blacklisted furnaces" were mostly situated in the city proper and residential areas.

If they were treated as required, Beijing residents would breath in 2,500-ton less of sulfur dioxide annually, the article reported.

In an effort to improve Beijing's air quality, about 13,000 small furnaces previously fueled by coal have been successfully transformed to use clean energy. Transformation of the remaining 3,000 small furnaces will be completed before 2008, Zheng said.