The amount of tritium residual in uranium bed was measured by methods of direct measurement, isotope exchange and dissolution. The standard deviation of the three methods was analysed under the present experimental condition, respectively. Results showed that the amount of tritium residual in the glass uranium was 2.68%, namely there was (0.0308±0.0003) mmol tritium per gram uranium. The standard deviation of PVT measurement method based on the state equation of the ideal gas was less than 0.95%, when the pressure was between 1500 and 133332 Pa. The efficiency of isotope exchange was only 2.84%, namely, the amount of less than 3% (molar fraction) tritium was exchanged out of the glass uranium bed by deuterium, and after isotope exchange proceeded time after time, its standard deviation was 7.35%. Dissolution method could measure tritium in the uranium bed completely, and its standard deviation was 6.49%.

Key words: uranium bed, tritium, amount of tritium residual