Abstract: STATIC EXPERIMENT RESEARCH ON A TYPE OF NUCLEAR WEIGH SCALE FITTED WITH LONG ROD RADIATION SOURCE AND LONG DETECTORFeng Gensheng Du Hongshan Li Guiqun Li Guihua Li Shushen(Department of Isotope, China Institute of Atomic Energy, Beijing 102413)ABSTRACTThe way using a long rod radiation source and a long ionization chamber to decrease the activity of radiation source for the nuclear weigh scale is analysed in terms of theory and the static comparison experiment is carried out, according to the basic principle and the actual situation. The experiment results show that the activity of 137Cs radiation source for the nuclear weigh scale can be decreased from original 3.0-3.7 GBq to 370 MBq while the measuring precision is not reduced.Key words nuclear weigh scale point radiation source long rod radiation source static experiment research