A national radiation dose registration system is proposed in this paper. In Japan, only one radiation dose registration system is partly effective. It is applied for workers in nuclear power plants which are under control of regulatory laws for nuclear reactors. The total system was proposed previously by the Committee for Compensation Claims of Nuclear Accidents. The reason for the delay in establishing a registration system for all radiation workers is supposedly a lack of effort to adjust differences among items in radiation protection laws and the promotion of public acceptance to atomic power. Items about dose recordings, record keeping and dose-record reporting in all of the radiation regulatory laws are compared to each other, and items were extracted for revision.

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The thermoluminescence (TL) response of CaF₂: Tm to ionizing radiation has been shown to be affected by the covering or bedding Teflon. The intrinsic TL response to ionizing radiation decreases when the phosphor is covered with thin Teflon plates used with automatic reading systems. The experimental results indicate that Teflon (1) influences the TL emission, (2) decreases glow curve peak heights, particularly the high temperature peaks, and (3) affects the glow curves depending on radiation energies and doses.

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The Nuclear Safety Commission (NSC) derived the unconditional clearance levels for concrete and metal arising from the operation and dismantling of nuclear reactors. The Japan Atomic Energy Research Institute conducted technical analyses to support the discussion by NSC. The clearance levels of 20 radionuclides were derived from 10μSv/y of individual doses by deterministic approach. In this approach, calculation models were established to assess individual doses resulting from 73 exposure pathways related to disposal and recycle/reuse, and realistic parameter values were selected considering Japanese natural and social conditions. The derived clearance levels of most radionuclides (e. g. γ-ray emitters such as ⁶⁰Co and α-ray emitters such as ²³⁹Pu) are nearly same as those shown in IAEA-TECDOC-855. However, some β-ray emitters such as ⁹⁹Tc and ¹²⁹I are smaller than those shown in IAEA-TECDOC-855.

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