Thirty-four construction sites in Shanghai were selected as pilot programs to take dust-control measures by installing online monitoring systems for 24/7 real-time reading of air quality.

"Records of construction sites' particulate matters as well as noise pollution will be available through the system online," said Hu Guoliang, an engineer from the Shanghai Environmental Protection Bureau.

Hu said the pilot program is the best option as enterprises can regard the monitoring system as a guide. "They're the first to know if the readings are too high," Hu told China Daily.

Earlier this year, authorities from the bureau said measures such as an emergency pollution-reduction plan have been applied to coal-fired power plants and chemical industries.

Shanghai's average density of PM2.5, particles smaller than 2.5 microns, reached 56 micrograms per cubic meter since the city posted its reading last June. The city's worst air was observed during Jan 16 to 18 when the air quality index, reached 254, followed heavy air pollution in Beijing.

Beijing's average PM2.5 density is between 80 to 90 micrograms per cubic meter.