The meteorological authority of China issued yellow alert in various cities. Yellow alert indicated the presence of fog that shows dangerous smog levels in the northern as well as western regions of China. The cities which were under the blanket of yellow alert included major ones such as Chengdu and Beijing. The alert mentioned that China was reeling under the effects of worst ever pollution record.
The Beijing Municipal Environmental Monitoring Center website declared that the density of the PM2.5 particulates crossed the 700 micrograms per cubic meter level in various parts of Beijing. According to the World Health Organization, the safe daily level is 25 micrograms per cubic meter.
Initially, it was found that the PM2.5 that is an indicator of the air quality had reached 500 point in certain monitoring stations. PM2.5 is an indicator of the extent of floating fine particles. The level of 350-500 is actually considered as hazardous. According to the recommendation of WHO, PM2.5 level should ideally be 20. This level was 19 in the New York City on 12 January 2013. The US embassy in Beijing monitoring the levels of pollution announced that PM2.5 exceeded the highest level of the record.
The fog led to cancellation of around 10 flights, delaying 5 flights in the meanwhile. At various airports in Beijing, the visibility was reduced to 100 metres. Road traffic on the highways was also disrupted.