In a bid to help clear the air for the Beijing Olympics, ten industrial polluters have been closed down. The factories included cement, steel and chemical plants.

The joint effort on emission control has yielded an initial effect. Beijing experienced 22 “blue sky” days, or days with fairly good air quality, in January. That was the best run of clear days since the year 2000, though persistent cold air was also cited as a major factor to keep the air clear.

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