Beijingers are to be warned of "haze" in daily weather forecasts so they can take measures to avoid air pollution.

The municipal meteorological authorities are to include the information on hazy days when the humidity is at, or under, 80 percent from February 1.

?Haze will be divided into three grades -- light, moderate and heavy, said Guo Hu, head of the Beijing Municipal Meteorological Station.

Light haze will be defined as visibility between five and 10 kilometers, moderate with visibility between two and five kilometers and heavy means visibility is under two kilometers.

Guo said haze formed when the concentration of dust, smog and other harmful matter was high in the air during days without wind.

Experts warn that haze contains substances harmful to the respiratory tract and lungs. The public is recommended to stay indoors during moderate and heavy days of haze.

Beijing reported 10 such days in December. This is one-third of the total recorded in the capital last year.

Shi Hanmin, head of Beijing Municipal Environmental Protection Bureau, said last week that local environmental authorities would take further steps to control air pollution and had set an ambitious target of 245 "blue sky" days this year after their beating the 2006 goal.

The authorities reported the annual target of 238 days with fairly good air quality had been reached on December 24 and recorded three more such days before the New Year.

Experts said rain in July and August led to the record number of good air quality days.

Du Shaozhong, deputy director of the bureau, attributed the achievement in part to intensified efforts made by environmental protection agencies to reduce pollution from coal burning.

According to the bureau's website the municipal government will put air quality improvement, the public's biggest concern, on top of its agenda this year.

Beijing launched the "Defending the Blue Sky" program in 1998 when the city had only about 100 "blue sky" days a year.

(Xinhua News Agency January 29, 2007)