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This work aims to experimentally report the radiation attenuation factors for four different clays (red, ball, kaolin and bentonite clays) at four selected energies (emitted from Am-241, Cs-137, and Co-60). The highest relative difference in the mass attenuation coefficient (MAC) is equal to −3.02%, but most of the other results are much smaller than this value, proving that the experimental and theoretical data greatly agree with each other. From the MAC results, the shielding abilities of the clay samples at 0.060 MeV follow the order of: bentonite > red > ball > kaolin. Thus, at low energies, the bentonite clay sample provides the most effective attenuation capability out of the tested clays. The half value layer (HVL) increases as energy increases, which suggests that, only a thin clay sample is needed to sufficiently absorb the radiation at low energies, while at higher energies a thicker sample is needed to shield the same amount of high energy radiated. Furthermore, bentonite clay has the lowest HVL, while the kaolin clay has the greatest HVL at all energies. The radiation protection efficiency (RPE) values at 0.060 MeV are equal to 97.982%, 97.137%, 94.242%, and 93.583% for bentonite clay, red clay, ball clay, and kaolin clay, respectively. This reveals that at this energy, the four clay samples can absorb almost all of the incoming photons, but the bentonite clay has the greatest attenuation capability at this energy, while kaolin clay has the lowest. [ABSTRACT FROM AUTHOR]

Researchers have tested the potential of various polymer composites for use in radiation shielding. They are light and non-toxic compared to Pb and have potential as shielding in diagnostic radiology where low-energy photons are predominantly used. This study documents the production of four composites using the combination of a base, i.e. high-density polyethylene (HDPE) polymer, and four other elements/compounds, i.e. molybdenum, molybdenum carbide, tungsten, or tungsten carbide. The resulting composites were synthesized in the form of 20 disks, each with a thickness of 2 mm. The disks were irradiated by a kilovoltage X-ray source (1.5 cm2 field size). The mass attenuation coefficient (μ m), half value layer (HVL), mean free path (MFP), and equivalent atomic number of the disks were measured. We found that supplementing HDPE with additives enhanced the attenuation of beams; the μ m values of the composites were higher than that of the pure HDPE polymer. The μ m values of the measurement and calculation results were in good agreement with each other, with an average error of 5.2%. Among the three additive concentrations that were tested, i.e., 5, 10, and 15%, the 15% concentration in HDPE yielded the best shielding efficiency. Since they possess smaller values of HVL and MFP, the polymer composites containing W and WC performed the best at attenuating the radiation beams. • HDPE with Mo, W, MoC, and WC as additives can replace Pb as radiation shield. • Performance of HDPE with three additive concentrations, 5, 10, and 15%, was tested. • HDPE with 15 wt% of additives shows the highest radiation shielding efficiency. • W- and WC-HDPE composites are the best radiation shield against X-rays. • Proposed HDPE polymers are nontoxic, easy to mold, and lightweight. [ABSTRACT FROM AUTHOR]