Determination of the details of technical standard concerning the transport of nuclear fuel materials outside the works or the enterprise

The determination is defined under the regulations concerning the transport of nuclear fuel materials outside the works or the enterprise. The least dangerous nuclear fuel materials designated by the Director General of Science and Technology Agency include, besides such materials listed and corresponding to the particular terms, natural or depleted uranium, natural thorium and their compounds whose surface is covered by corrosion resistance metal. The permissible density of surface stipulated by the Director is 1/100,000 micro-curie per centi-meter2 for radioactive substances not emitting alpha rays and 1/10,000 micro-curie per centi-meter2 for radioactive substances emitting alpha rays. General test conditions of A, BM and BU type of loads are in detail provided for. The nuclear fuel materials defined by the Director not as fission materials are uranium 233 and 235, plutonium 238 or 241, whose quantity or combined quantity of such substances do not exceed 15 grams and natural or depleted uranium. The permissible accumulative dose specified for employees is the figure (unit rem) calculated by the formula D=5 (N-18), when D means the permissible accumulative dose and N number of the age. The permissible exposure dose shall be 3 rem for 3 months for employees and 1.5 rem for a year for persons other than employees. (Okada, K.)