TRITIUM MONITORING-SYSTEM FOR NEAR AMBIENT MEASUREMENTS

This paper describes the current status of research on an improved tritium measurement system at the Oak Ridge National Laboratory (ORNL) for the U.S. Navy. Present tritium-in-air monitoring systems installed by the Navy can reliably measure to less than 10 muCi/m3, but medical and safety issues are pushing measurement needs to below 1 muCi/m3, which is equivalent to 1-10 nCi/ml in liquid samples, using calcium metal converter. A significant effort has been expended over the past 10 years by the Navy RADIAC Development Program at ORNL on various schemes to improve the detection of tritium in both air and liquid at near ambient levels. One such scheme includes a liquid flow-through system based on an NE102 sponge scintillator with dual photomultiplier tubes for tube noise rejection.