BEIJING, Jan. 4 (Xinhua) -- Beijing saw less heavily polluted days and reducing average concentration of hazardous gas and particles in 2018, local authorities said Friday.
The city's average PM 2.5 density dropped to 51 micrograms per cubic meter in 2018, down 12.1 percent year on year, according to Beijing Municipal Ecological Environment Bureau.
The city had 15 heavily polluted days last year, comparing to 58 in 2013.
Since the central government rolled out an action plan on air pollution control in 2013, Beijing has taken measures such as encouraging clean energy and upgrading factories.
Average concentration of sulfur dioxide, PM2.5, PM10 and nitrogen dioxide in the city dropped by 77.8, 42.7, 27.8 and 25 percent respectively from 2013 to 2018.
Li Xiang, official with the bureau, said the city still faced excessive air pollutant emissions, and there was still much to do to improve air quality.
"Currently, the city is focusing on the control of heavy diesel vehicles, dust and volatile organic compounds, and has been cooperating with neighboring areas to ease air pollution," he said.