Characterisation of reference materials for radioactivity with assigned values traceable to the SI units.

The Institute for Reference Materials and Measurements participates in an IAEA co-ordinated project to upgrade Analytical Quality Control Services intercomparison materials to reference materials. The principal objective is to ensure that assigned property values are traceable to the International System of Units. General principles and practical mechanisms for achieving this traceability are described.

Validation of methods for the determination of radium in waters and soil.

This article describes the advantages and disadvantages of several analytical methods used to prepare the alpha-particle source. As a result of this study, a new method combining commercial extraction and ion chromatography prior to a final co-precipitation step is proposed. This method has been applied and validated on several matrices (soil, waters) in the framework of international intercomparisons. The integration of this method in a global procedure to analyze actinoids and radium from a single solution (or digested soil) is also described.