PERFORMANCE PARAMETERS OF TWO QUANTULUS 1220 FOR LOW LEVEL TRITIUM MEASUREMENTS |
National Research and Development Institute for Cryogenics and Isotopic Technologies – ICSI Rm. Valcea, Code 240050 - Rm. Valcea, Uzinei 4, PO 7 Raureni, Valcea, Romania
Liquid scintillation counting (LSC) is the most commonly used technique for measuring low-energy beta emitters, namely for tritium. ISO 9698/2010, International Standard specifies the conditions for the determination of tritium activity concentration in samples of environmental water or of tritiated water ([3H]H2O) using liquid scintillation counting. This paper presents the results of a comparative study conducted with four Tritiated standard solutions, using two ultra-low level liquid scintillation spectrometers Quantulus 1220TM. We investigated the variation of three measurement parameters: the counting efficiency, the figure of merit and the background counting rates. Measurements were performed using two ultra-low level liquid scintillation spectrometers Quantulus 1220TM, one in service from 1998 manufactured by Wallac (Q1) and the other from PerkinElmer in service starting with 2011 (Q2). After measurements made we had 25 observations for Q1 and 63 observations for Q2, respectively.
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