China’s capital Beijing issued a “red alert” for pollution. Beijing’s second red alert comes after a landmark climate agreement was reached in Paris earlier this month.
The city’s first red alert was issued on Dec. 7, restricting traffic and halting outdoor construction.
The Beijing Meteorological Service said in a statement vehicle use would be severely restricted, and that fireworks and outdoor barbecues would be banned. It also recommended schools cancel classes.
City residents have previously criticised authorities for being too slow to issue red alerts for heavy smog, which often exceeds hazardous levels on pollution indices.
Meteorological authorities have said this time the smog is expected to exceed 500 micrograms per cubic metre.
What are PM 2.5 particles?
- Particulate matter, or PM, 2.5 is a type of pollution involving fine particles less than 2.5 microns (0.0025mm) in diameter
- A second type, PM 10, is of coarser particles with a diameter of up to 10 microns
Some occur naturally – e.g. from dust storms and forest fires, others from human industrial processes - They often consist of fragments that are small enough to reach the lungs or, in the smallest cases, to cross into the bloodstream as well
- A build-up of PM2.5 in the lungs has been associated with causing respiratory illnesses and lung damage
