Notification determining the technical detail concerning disposal of nuclear fuel materials outside the works or the enterprise

The notification is defined under the regulations concerning the disposal of nuclear fuel materials outside the works or the enterprise. The method designated by the Director General of Science and Technology Agency includes specified processes of hardening in a metal vessel with hydraulic cement or combined materials of hydraulic cement, aggregate and additive. The limit of concentration of radioactivity is defined by the director as 1 curie per ton for radioactive substances emitting alpha rays, 0.1 curie per ton for radium 226 and polonium coexisting with lead 226, 100 curie per ton for radioactive substances not emitting alpha rays with half-life of more than 6 months and 1 million curie per ton for tritium and radioactive substances not emitting alpha rays with half-life of less than 6 months. The radiation dose stipulated by the Director is 50 milli-rem per hour on the surface of thrown waste. The permissible accumulative dose is specified by the Director to be the figure (unit rem) calculated by the formula D=5 (N-18), when D means permissible accumulative dose and N number of the age. The permissible exposure dose is defined by the Director for the employees to be 3 rem for 3 months, and for persons other than the employees 1.5 rem for a year. (Okada, K.)