City authorities issued an orange alert, the second highest of four danger levels. On November 30, Beijing was facing the worst air pollution since early 2015.

The orange alert was issued a day after the level of small particles (so called PM 2.5 particles with a diameter of 2.5 micrometers or less) reached 274 micrograms per cubic meter. The World Health Organization (WHO) considers only 25 micrograms to be a safe level. Meanwhile, trucks are barred from entering the capital city. Construction sites should stop operation and avoid handling construction wastes and other materials.

The city authorities urged residents to stay at home. In case they have to go out, they are recommended to wear tight-fitting face masks.

On December 1, 2,000 industrial plants in Beijing had to stop operation as the government is making efforts to reduce emissions of hazardous particles in the air and tackle the abnormal level of smog.

Locals say that visibility was cut to several hundred meters as buildings receded into thick smog.

The city said the levels of hazardous tiny PM2.5 particles in the air exceeded 600 micrograms per cubic meter at several monitoring sites late Monday afternoon.

Western media noted a funny coincidence. Heavy smog covered the capital exactly at the moment when President Xi Jinping was participating in the UNO climate summit in Paris. By the way, China’s head pledged to improve the environmental situation in Beijing.

Importantly, nowadays China is on the list of the most polluted countries in the world. A large number of factories makes it complicated clean the air. In 2013, carbon dioxide emissions in China totaled 10 billion tons. This indicator was twice lower in the United States.