Beijing launched a one-month household registration survey on Sunday in preparation for the once-a-decade census of China, the world's most populous country, which begins in November.

Beijing launched a one-month household registration survey on Sunday in preparation for the once-a-decade census of China.

A total of 100,000 uniformed census takers will go door-to-door in Beijing from Aug. 15 to Sept. 15, along with policemen, to check each household's current residential information, said a spokesman with the sixth national population census' Beijing office.

Foreigners and residents of Hong Kong, Macao and Taiwan will also be surveyed for the first time, except those on short-term business or sightseeing trips, according to a census regulation jointly issued by the State Council and the National Bureau of Statistics in May.

"This is because the upcoming national census seeks to survey 'every natural person' in China and Chinese citizens who live abroad but have not obtained long-term living permits," said Su Hui, director of the office.

The survey aims to count the total number of Beijing residents and to correct false household registration information and provide accurate information for the sixth national census, he said.

Experts say that many households do not unregister their deceased family members so they might continue collecting social insurance funds from the government. Also, some children born in violation of the country's "one child" policy were also not registered.

All information collected in this survey will be kept confidential, and will not be used for other purposes, Su added.

Since the founding of the People's Republic in 1949, China has conducted national population censuses in 1953,1964,1982,1990 and 2000.

The last census, a decade ago, set China's population at 1.29533 billion people.