Several analytical techniques have long been used for uranium concentration and isotopic ratio determinations within the many Department of Energy laboratories located throughout the United States. Thermal ionization mass spectrometry (TIMS) has historically been the technique of choice for isotopic ratio measurements, primarily due to its capability for high precision. For uranium concentration work, the list of techniques is long and varied. Each of these methods has its own strengths and weaknesses, which can become critical in the analysis of difficult sample matrices such as sludges, oils, and mixed wastes.
From a practical standpoint, the use of inductively coupled plasma-mass spectrometry (ICP-MS) for uranium measurements is an attractive alternative to techniques such as TIMS and fluorimetry, due to its higher throughput, less demanding sample preparation requirements, and ability to measure both concentration and isotopic ratio on the same sample. There would appear to be numerous real-world situations in which ICP-MS would be preferable to these older methods. In order to determine the precise conditions under which each technique should be utilized, a comparative evaluation of several techniques as applied to the determination of uranium in industrial waste samples has been performed.