Beijing's air quality has continued to improve over the first 10 months this year, with the number of days of good air quality totaling 221. That's 31 more than the same period last year, according to the Beijing Ecology and Environment Bureau.

The environmental authority recently published the air quality report from January to October, noting that the concentration of four major pollutants had hit a record low.

The cumulative concentration of fine particles — PM2.5 — averaged 39 micrograms per cubic meter for the first 10 months, a year-on-year drop of 7.1 percent.

Local authorities will continue to focus on key sources of pollution, including heavy diesel vehicles, volatile organic compounds and dust, as the city enters the winter season.

Beijing is coordinating its economic and social development with air pollution prevention and control, giving the green light to companies with superior ecological performance and fewer emissions, thereby encouraging enterprises to strengthen their daily management and upgrade pollution-reduction techniques.