A secondary air-quality monitoring station was established in the Olympic Green on October 28.

Located on the lawn of the National Indoor Stadium, the station was intended to provide information necessary for any adjustment to the construction techniques during the construction of the Olympic venues, as well as enhancement of the environmental control during the Games.

The Beijing Municipal Environmental Protection Bureau (EPB) introduced the air-quality automatic monitoring system from U.S. in the early 80s, and has by far instituted 24 secondary stations in the city.

The Beijing Environmental Protection Monitoring Center, an EPB subsidiary that controls all the secondary stations, releases weather report and forecast through news media on a daily basis. The daily report adopts air pollution index (API) to deliver the average air condition for the last 24 hours, while the forecast tells the most likely air condition(s) in the next 24-36 hours in the fashion of pollution index range.