Bioassey technique in atomic power plants, (1)

Bioassey is required for determing a worker's exposure to radioactive material. A quick analysis technique for assay of radioactivity in urine was investigated, and a new monitoring system using a large volume well-type plastic scintillation detector was developed. The background count rates of this system is not influenced by the natural radio nuclide 40K in urine, and the artificial radio nuclides (60Co, 58Co, 137Cs, 59Fe, etc.), of which concentration is about 1--2 nCi/100 ml, can be detected. (author)