Abstract
The Kanazawa National Hospital had designed and constructed the radiation booth for the telecobalt treatment, that had been supposed almost complete in regard to the protection from radiation, and the authors conducted the telecobalt therapy in it. In the mean time, a 19 years of old technician, working in the telecobalt therapy booth, developed the symptoms of radiation injury with peculiar clinical course and blood picture. While this radiation hazard occurred subsequent to 2 months of engagement in the telecobalt control booth, the dose of the radiation, to which he had been exposed in that period, was 52mr at the largest level per week, which is far below the International Maximal Permissible Dose, i. e., 300mr per week.
Considering from this case, the authors deem this international level, i. e., 300mr per week, should be revised to one-sixth or 50mr.
