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Updated: Feb 27, 2026

Irradiator Commissioning and Dosimetry for Assessment of LQ α and β Parameters, Radiation Dosing Schema, and in vivo Dose Deposition

Irradiator Commissioning and Dosimetry for Assessment of LQ α and β Parameters, Radiation Dosing Schema, and in vivo Dose Deposition

Published on: March 11, 2021

クリティカル事故における24Na比放射能から実効線量への換算係数

Munehiko Kowatari¹

¹Department of Radiation Measurement and Dose Assessment, Institute of Radiological Sciences, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan.

Radiation protection dosimetry

|February 25, 2026

Abstract:

New conversion coefficients relating 24Na specific activity in the human body induced by neutron exposure to the corresponding effective dose are presented to estimate public exposure in criticality accidents. The coefficients were calculated using state-of-the-art mesh-type phantoms developed by the International Commission on Radiological Protection (ICRP) and the Particle and Heavy Ion Transport code System code. Calculations were performed for all irradiation geometries defined by the ICRP, with monoenergetic neutrons ranging from thermal energies to 20 MeV. These newly derived coefficients enable a more accurate assessment of neutron radiation exposure to the general public in criticality accidents.

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Characterization of Recombination Effects in a Liquid Ionization Chamber Used for the Dosimetry of a Radiosurgical Accelerator

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