The air quality of Seoul was found to be the second worst among the world’s major cities on Tuesday morning.
 
According to Air Visual, a multinational community that provides air quality data, Seoul’s Air Quality Index(AQI) stood at 179 as of seven a.m. Tuesday. The figure was the second highest among key cities after India’s New Delhi whose index stood at 187.
 
Kolkata, another Indian city, and the Pakistani city of Lahore jointly came in third followed by China’s Chengdu and Beijing.
 
AQI is produced by calculating the amounts of air pollutants, including fine particulate matter, particulate matter, carbon monoxide, nitrogen dioxide, sulfur dioxide and black carbon. The higher the index, the worse the air quality.
 
A fine particulate matter watch that was issued for Seoul was lifted at eleven a.m. on Tuesday after being in place for 13 hours.