RadScan 600-a portable instrument for the remote imaging of gamma contamination: its design and use in aiding decommissioning strategy

BNFL Instruments RadScan 600 has been developed to allow the remote surveying of gamma radiation in a wide variety of environments. The device is based on a CsI crystal located in a tungsten collimator and is capable of detecting gamma rays with energies between 100 keV and 10 MeV. A colour CCD camera produces a visual image of the of the area undergoing survey. The key technical components of the device are described. The RadScan 600 has been used on a number of nuclear plants currently being decommissioned at Sellafield. The application of the device to the monitoring of a Windscale Pile chimney is presented. The monitoring of the chimney using RadScan 600 aided the decommissioning team to develop their strategy for the future decommissioning of the chimney.