CHARMS is a mobile assay and measuring system for making laboratory quality measurements of drums, waste bags and other waste objects in the field. It consists of a trailer with a laboratory/office and a heavy-duty turntable. The detection system employs a high-resolution, high purity Germanium (HPGe) detector with a large crystal diameter to enhance gamma ray detection. The HPGe detector is collimated and shielded to reduce the effect of the radiation background and radioactivity from other objects. The shielded detector system is mounted within the laboratory/office with a direct view of objects placed on the turntable,with an integral load cell for weight measurement, has a capacity of 2 metric tonnes.