BEIJING — Beijing reported 206 good air days in the first nine months of the year, an increase of nine days year-on-year, said the municipal ecology and environment bureau on Oct 12.

The monthly reading for PM2.5 in September fell to 18 micrograms per cubic meter, and the city has set an air-quality record with its cumulative concentration of PM2.5, a main gauge of air pollution, dwindling to 33 micrograms per cubic meter in the first three quarters, according to the bureau.

In the January-September period, Beijing has taken a variety of measures to tackle air pollution, including phasing out outdated fuel-powered vehicles and supervising vehicles operating on diesel.

Efforts were also made to enhance the supervision of factories and construction sites.

PM2.5, which refers to airborne particles smaller than 2.5 micrometers in diameter, poses serious health risks.