各種建築材料のγ線減弱係数および線量ビルドアップ係数

抄録

The present paper describes the γ-ray attenuation coefficient and the dose buildup factor of various building materials, which are of great importance for estimation of the shielding effect of residential houses against γ-rays.
The linear attenuation coefficients were measured for 19 building materials with γ-rays and filtered X-rays at energies ranging 44-1, 250keV. A corresponding atomic number, Z_cor, was defined as an atomic number of the element having the mass attenuation coefficients akin to those of the material. According to Z_cor, materials were classified into two groups: one is Z_cor=7-9 and the other is Z_cor=13-16.
The dose buildup factors were measured for 4 materials selected from each material group with γ-rays and filtered X-rays at energies ranging 68-1, 250keV. It was found for the thin materials such as ordinary building materials, that the dose buildup factor could be represented approximately by the linear formula, B_D=1+αμt, and α was characterized by both γ-ray energy and material group.