Optimization Method to Determine Gross Alpha-Beta in Water Samples Using Liquid Scintillation Counter

Abstract

Liquid scintillation counting (LSC) is an adequate nuclear technique to determine radioactivity levels, as verified by this study for the determination of the gross alpha and beta activities of aqueous samples because of its simplicity and low associated cost comparison with other techniques. This paper discusses a new approach to the monitoring of gross alpha and gross beta activities in water. The method consists of using pulse decay discrimination (PDD) liquid scintillation counting LSC of 2 ml of the sample after conditioning with 12 ml of AB-Ultima Gold LSC cocktail, and PDD 139 condition. Different factors that affected on the counting efficiency were studied such as quench reaction, volume of sample, and type of vial. The gross alpha and gross beta particle activity measurement using 40 K and 243 Am with different activities concentration for efficiency determination. The calculated detection limits were 0.07 Bq/l and 0.12 Bq/l for gross alpha and gross beta respectively for 500 min measurements of samples produced by concentration of one liter of water.

Alpha and beta spillover in liquid scintillation counting analysis of urine samples

“…Radiochemists use LSC to analyze gross alpha/beta activities in different matrices [ 7 – 9 ]. There are some publications regarding the quenching and PSA/PDD setting effects on the misclassification of alpha and beta events [ 10 , 11 ]. However, there is no information on how activity level can affect the alpha/beta spillover.…”

An application of LSC method for the measurement of gross alpha and beta activities in spiked water and drinking water samples

“…Before counting gross alpha and beta activities in LSC, pulse shape analysis (PSA) is performed to fi nd the optimum PSA value [1][2][3][4][5][6][7]. PSA is a separation technique which depends on the method that takes the tail charge of the scintillation pulse into account and compares it with the total charge.…”