The radionuclide 6 8 Ga is mainly a positron emitter (89.2%), with a half-life of 67.7min. It is used in nuclear medicine, being chemically extracted from the mixture 6 8 (Ge+Ga); its precursor, 6 8 Ge, disintegrates 100% by electron capture, with a half-life of 270.8d (Table of radionuclides, comments and Evaluation).A 4πβ-γ coincidence method was used for standardization, with a 4π proportional β-detector and a NaI(Tl) γ detector. Registration of the capture radiations was avoided using foil absorption and a high β threshold. Using supplementary foils for positron absorption, extrapolation graphs were obtained, with a mean slope of -4.4%. Care was taken to compensate for the loss of 6 8 Ge during the preparation of solid sources for measurement. A combined uncertainty of 1.1% was estimated.