Tritium measurement in nuclear waste is a key to determine the type of repository. This paper describes the methodology used to validate tritium measurement in various matrices using pyrolysis method with a new instrument available in the market. The efficiency obtained for tritium recovery in aqueous matrix, oil and concrete are respectively higher than 95%, 93% and 85%.

Radioactive waste management is nowadays, after nearly 50 years of concern, a technical and economical challenge faced by existing nuclear power countries. In decommissioning of nuclear facilities after removal of the nuclear equipment (laboratory materials, glove boxes, etc.), the radioactive inventory of the various building materials is needed to state the working condition for dismantling. Thus, characterization is essential for decommissioning and moreover for radioactive waste classification and management. A radionuclide imaging technique, the Digital Autoradiography (DA), also known as storage phosphor technology, has been studied for decommissioning projects because of its advantages such low price, easy utilization and sensitivity. DA has been proven to be an efficient technic in localization of beta emitter (especially C-14 and H-3) contamination remaining in nuclear facilities under dismantling. Samples have been collected where C-14 or H-3 have been observed by DA and analyzed by the classical technique : pyrolysis followed by liquid scintillation counting. Real applications to classify potential waste coming from a laboratory under dismantling are described in this paper.