(Yicai Global) Oct. 17-- Beijing suffered another bout of extreme air pollution in October, with haze enshrouding the capital from Oct. 14-16, and with the worst smog on the 14th and 15th.
Weather conditions caused pollutants to gather in north China's atmosphere. On Oct. 13, Beijing's environmental protection bureau reported that its heavy air pollution emergency response headquarters issued a blue warning at 4.00 PM on Oct. 13, escalating this to blue to yellow the next day.
The Xinhua News Agency reported that visibility in Beijing was only about one kilometer -- less than 500 meters in some places -- in the early morning of Oct. 14. The air quality index hit 367 at 2.00 PM.
The environmental protection authorities ordered relevant organizations to tighten up dust control, and halted all earthwork, construction and demolition activities in the city. Cleaning was intensified at all important roads, with a ban on open-air burning and stubble burning. Air quality is expected to slowly improve, with a weak cold front setting in on the evening of Oct. 16.
According to China's existing "national standards" for air quality control, a heavy air pollution event occurs if PM 2.5 concentration is greater than 150 micrograms/cubic meter, i.e. equivalent value of the air quality index (AQI) exceeds 200. Severe pollution occurs if the fine particulate matter (PM 2.5) concentration passes the threshold of 250 micrograms/cubic meter.