Enrichment of Tritium by Thermal Diffusion and Measurement of Dated Antarctic Snow Samples

A thermal diffusion column allows a recovery of 99+/-1 percent of the tritium originally contained in about 50 liters at standard temperature and pressure of hydrogen gas in a final volume of 3.8 liters over a 2-day period. After a tenfold enrichment by electrolysis, a tritium concentration of 10(-18) with an experimental error of a few percent may be measured with a low-level Geiger counter. The results on some well-dated Antarctic snow samples (between 1941 and 1953) are in general agreement with published data.