A portable whole-body counter has been constructed from the over 10 years experience of routine operation of a heavily shielded whole-body counter. The portable counter is designed to operate automatically when a subject is seated in an upholstered chair lined with 12mm thick lead. The detector has a 3φ×3 in. sodium iodide scintillation crystal mounted in a 50mm thick lead shield which is opened only in direction of the chair. Signals from the detector are analyzed with a three channel pulse hight analyzer the covered energy ranges of which can be varied with the objective nuclide. Minimum detectable amounts are 34nCi for Cs-137 and 17nCi for Co-60 for 10 minutes counting with the three channel pulse hight analyzer, 12nCi and 13nCi for 40 minutes with a multi-channel. Those values are well below the investigation levels given by ICRP Publication 10.
The survey of material composition of the low level radioactive solid waste was performed in connection with the design work of the new incinerator in Tokai Establishment, JAERI. Five large facilities were selected as the representation of more than 20 facilities, and 500 packages were chosen out of 2, 189 packages discharged during 2 months, June and July 1973. They consisted of the combustible and compressible waste but not included filters and contaminated equipments. The survey showed following result; plastics 33%, waste cloth 24%, paper 18%, rubber 9%, clothes 5%, timber 1% (total of above mentioned materials 89%), metal 7%, glass 2%, concrete and sand 2%. Eighty-nine % of the total quantity is combustible material in principle, then it will be expected that the incineration treatment get a wider application to reduce the volume of final disposal.