Standardization of pure-beta emitting and electron-capture radionuclides by liquid scintillation counting

A short account is given of the liquid scintillation coincidence system developed at OMH for the standardization of pure-beta emitting and electron-capture radionuclides. Our experience of direct activity concentration measurements is outlined for 14C (coincidence and summing methods tested by activity measurement of 60Co); 55Fe (efficiency tracer technique using 54Mn as tracer); 3H (efficiency tracer technique using 54Mn as tracer). The uncertainty components are discussed in detail, and can be reduced by undertaking several more precise corrections.