Liquid scintllation counting (LCS) techiques are widely used for the calibration of beta and electron-emitter radionuclides. This technique has been promoted by the development of the NIST/CIEMAT standardization method and by the Triple to Double coincidence ratio (TDCR) method. these two models are based on common computation models. The aim of this project is to use LCS for the standardization of a low-energy pure-beta-emitter: Ni-63 and a low-energy electron and X-rays emitter Fe-55. These radionuclides have been choosen because their standardization is of practical interest and could hardly be done by other means.
The participation of NIST, BIPM, RC and NAC is accepted by all the european partners.