Evaluation of the portable liquid scintillation counter Triathler™ for characterising small-scale nuclear incidents

The portable liquid scintillation counter Triathler™ was used under laboratory conditions to perform gross alpha and beta measurements as well as wipe tests. The results of these measurements were compared with results from certified methods that are routinely used at our laboratory. Background measurements with different scintillation cocktails using different counting modes were performed and the occurrence of luminescence after sample preparation in the lower energy regions was evaluated. An increased background was observed shortly after the mixing of the distilled water and the scintillation cocktail. The scintillation cocktail Hisafe 3 proved to be most suitable for on-site applications with the Triathler.