Year
2003
Abstract
Two new XRF screening instruments – TRIPOD and the FEI 8030C TXRF analyzer have been installed at the IAEA Safeguards Analytical Laboratory. The TRIPOD is an energy dispersive XRF analyzer used for screening environmental swipe samples for the presence of uranium. The system provides information about total uranium quantity on the swipe and the distribution of uranium and other elements on the swipe surface. The swipe is measured horizontally in 280 positions with a total measurement time per swipe of 4 hours. The uranium detection limit is 30 ng. A total- reflection X-ray fluorescence analyzer, model FEI 8030C, is used to screen for uranium, plutonium and other elements in samples prepared for TIMS bulk or SIMS particle analyses. For TXRF measurements samples are decomposed using wet chemical decomposition and/or plasma ashing followed by acid dissolution. After clear homogenous solutions have been obtained aliquots of up to 5%in volumes as large as 5 micro-L are applied to precleaned quartz planchets. The uranium detection limit for environmental cotton swipe samples is 15 pg. This paper reports on the technical parameters of the instruments and gives typical examples of measured environmental samples.