Abstract: Due to the difficulty in preparation of homogeneous radioactive waste drum with large volume, the detection efficiency of segmented γ scanning (SGS) device is scaled usually with indirect approaches. Shell source method is one of best ways, which uses linear source as the principal part. It is not so complicated for the preparation, and the structure is flexible. Based on the comparison of measurement results from uniform drums and drums prepared with shell source method, it is proved that they are equivalent in the calibration of efficiency. The latter can be taken as the reference source of SGS device.