BEIJING — Air pollution levels in China's notoriously dirty capital have hit dangerous levels, with cloudy skies blocking out visibility and warnings issued for people to remain indoors.
Local authorities have warned the severe pollution is likely to continue until Monday.
The Beijing Municipal Environmental Monitoring Center has reported air-quality readings between 176 and 442 from its monitors throughout the greater Beijing area since Friday. The monitors measure the level of air-borne PM 2.5 particulates, which are tiny particular matters considered the most harmful to health.
The air is considered good when the reading is at 50 or below but hazardous with a reading between 301 and 500, when people are warned to avoid outdoor physical activities.
Monitors in urban Beijing all reported readings above 300 on Friday, and the center real-time readings showed Beijing remained heavily polluted on Saturday with readings as high as 478 at 3 p.m.
Monitors at the U.S. Embassy in Beijing recorded an off-the-chart air-quality reading of 699 as of 3 p.m. Saturday.
Readings are often different in different parts of the city and because the instruments used to measure the pollution levels are different.
According to rules issued by the city government in December, all outdoor sports activities are to stop and factories have to reduce their production capacity if Beijing's official air-quality reading goes over 500.
Air pollution is a major problem in China with its rapid pace of industrialization, reliance on coal power, explosive growth in car ownership and disregard to environmental laws.
In Beijing, authorities have blamed a lack of wind and foggy conditions for the high concentration of air pollutants.
Several other cities, including Tianjin on the coast east of Beijing and southern China's Wuhan city also reported severe pollution over the last several days.