1 Scope

This document describes a generic test method for measuring alpha emitting radionuclides, for all types of samples (soil, sediment, construction material, foodstuff, water, airborne, environmental bio-indicator, human biological samples as urine, faeces etc.) by alpha spectrometry. This method can be used for any type of environmental study or monitoring of alpha emitting radionuclides activities.

If relevant, this test method requires appropriate sample pre-treatment followed by specific chemical separation of the test portion in order to obtain a thin source proper to alpha spectrometry measurement.

This test method can be used to determine the activity, specific activity or activity concentration of a sample containing alpha emitting radionuclides such as ²¹⁰Po, ²²⁶Ra, ²²⁸Th, ²²⁹Th, ²³⁰Th, ²³²Th, ²³²U,²³⁴U, ²³⁵U, ²³⁸U, ²³⁸Pu, ^239+240Pu, ²⁴¹Am or ^243+244Cm.

This test method can be used to measure very low levels of activity, one or two orders of magnitude less than the usual natural levels of alpha emitting radionuclides. Annexes B of UNSCEAR 2000 and UNSCEAR 2008 (References [4] and [5]) give, respectively, typical natural activity concentrations for air, foods, drinking waters and, soils and building materials. The detection limit of the test method depends on the amount of the sample material analysed (mass or volume) after concentration, chemical yield, thickness of measurement source and counting time.

The quantity of the sample to be collected and analysed depends on the expected activity of the sample and the detection limit to achieve.