PROPORTIONAL COUNTER ASSAY OF TRITIUM IN GAS CHROMATOGRAPHIC STREAMS

An investigation was made on the factors that affect the accuracy and reproducibility of propertional counter analysis of tritiated radioactive components in gas chromatographic streams. The behavior of helium- methane and helium-propane fiow mixtures is discussed extensively. The critical point for accurate assay is maintaining constant efficiency for tritium in various molecular forms. Variations in detection efficiency arise especially from coincidence losses at high count rates and from composition changes in the operating counter gas during the passage of a macroscopic peak. (P.C.H.)