Hebei Province, which neighbors Beijing and is known for severe winter smog, has pledged to bring down the average PM2.5 level by 5 percent this year.
Xu Qin, governor of the province made the announcement on Thursday, when he delivered a government work report at the ongoing local parliamentary session.
Hebei recorded its best air quality levels last year since pollution control measures were implemented five years ago. The average PM2.5 in 2017 was 65 micrograms per cubic meter, down 7.1 percent year on year, marking a decrease of nearly 40 percent from 2013.
PM2.5 is a measure of the density of hazardous particulate in the air. The World Health Organization recommends an annual PM2.5 level of 10 micrograms per cubic meter.
Hebei also recorded improvements in the density of other major pollutants such as sulfur dioxide, nitrogen dioxide and PM10, with sulfur dioxide down 63.5 percent compared with 2013.
While the number of heavy pollution days decreased from 80 in 2013 to 29 in 2017, the province also enjoyed 202 "good air" days last year, 73 more than in 2013.
The province will continue to make efforts to fight smog and lower the density of PM 2.5 and other major pollutants this year, by promoting clean energy heating, monitoring emissions from factories, retiring 80,000 old vehicles and promoting 30,000 new energy ones, according to the government work report.