The Zhongshan Bureau of Ecology and Environmental recently released the city's air quality report for the third quarter of 2019. 

According to the report, there were 92 effective monitoring days in Zhongshan in the third quarter, with the air quality been excellent for 43 days and severely polluted for 0 days. 

In the third quarter, 70.7% of the days met the standard of the air quality index (AQI) on average. Compared with the same period last year, the proportion of days when the air quality of the whole city met the standard dropped by 13.0%. 

The main air pollutant in the whole city was eight-hour ozone (O3-8h), followed by fine particulate matter (PM2.5) in the third quarter.