Measurement of tritium with high efficiency by using liquid scintillation counter with plastic scintillator

The detection efficiencies of tritium samples by using liquid scintillation counter with hydrophilic plastic scintillator (PS) was approximately 48% when the sample of 20 μL was held between 2 PS sheets treated by plasma. The activity and count rates showed a good relationship between 400 Bq to 410 KBq mL−1. The calculated detection limit of 2 min measurement by the PS was 13 Bq mL−1 when a confidence was 95%. The plasma method for PS produces no radioactive waste.