The Chinese government will issue real-time air quality monitoring data in 74 cities starting Jan. 1, 2013, the Ministry of Environmental Protection said Friday.

Notably, the data will include PM2.5, a gauge that monitors fine particulate matter with a diameter of 2.5 microns or less, the ministry said.

Wan Bentai, chief engineer with the ministry, said data on major pollutants in the air, namely sulfur dioxide, nitrogen dioxide, ozone, carbon monoxide and particulate matter, will be released on an hourly basis.

The data will be collected via 496 monitoring sites in the 74 cities, he said.

Information on particulate matter available in China used to be limited to PM10, or particulate matter 10 microns or less in diameter.

There has been surging public demand in China in recent years for data on PM2.5, which experts believe is more hazardous to people's health than PM10 as it can penetrate deeper into the lungs.

According to Wan, under the new arrangement, more information on air quality will be monitored and publicized than before, thus offering a more accurate picture of air quality.

China is proceeding with its urban air quality monitoring program in stages and aims to cover all prefecture-level cities by 2016.