Use of ultrasonic instruments in chemical plant containing hazardous materials

Ultrasonic instruments are described that were developed for use in a nuclear fuel reprocessing plant and had therefore to be extremely reliable, easy to maintain and remotely operated. The empirical relationship, for the measurement of the concentration of uranium plus plutonium in solution in an organic solvent, is given. An important feature of the instrument is that the containment of the plant is not breached. The measurements are made by pulse techniques. Application to a number of different problems is described, including level and interface detection, use under flammable conditions and use at high temperatures. (U.K.)