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Radiation education is necessary for a wide variety of people, such as radiation workers particularly for students of secondary school and higher education institution who learn radiation sciences. The fact that we could not see or feel radiation makes it difficult to understand it. The use of radiation trajectories shown on a personal computer should be useful to overcome this difficulty. In order to understand radiation behaviour inside the material, we have developed a Simu-Rad (Copyright: LY2018002738) by using Monte Carlo simulation programme. One who has no programming knowledge is able to simulate photons in a material through the developed programme. The program could become a computer aided learning tool for radiation related courses. We aim to facilitate lecturer from ‘The Traditional Classroom’ to ‘The Flipped Classroom’ for radiation education concerning in the era of IR 4.0. To validate our radiation simulator, we calculate photon linear attenuation coefficient (µ) of an aluminium material which commonly used as a filter in diagnostic radiology. µ is one of the main characteristics to understand how the radiation attenuated inside the materials. We calculate at energy photon of 662 keV (Cs-137 radiation source) to compare our results of µ with the XCOM database. Consequently, the results from the developed simulator comparable with the database verified our programme to be used for radiation study.

Most radiology departments utilize ordinary concrete and lead for radiation shielding as the primary radiation can be reduced through photon absorption. There are many studies done focusing on the transmitted photons that penetrate the shielding materials for radiation shielding. However, the scattering from the shielding materials would be ignored. When high-energy photons impinge on thick shields, most of the incident energy is absorbed in the shielding materials, but some of it can also be deflected sideways or in a backward direction. This is important as the backscatter radiation can contribute to unnecessary additional radiation dose to healthcare workers. Hence, this study evaluates several shielding materials namely aluminium, iron, copper, lead, ordinary concrete, and heavy concrete particularly for its attenuated and scattered photons for radiation shielding. The shielding materials were evaluated using the Monte Carlo simulation, specifically PHITS code. In the simulation, all shielding materials were modelled as a fixed 30 x 30 cm rectangular shape with a fixed thickness of 10 cm. Mono-energy and pencil beam photon energies ranging from 100 keV until 1 MeV were directed to the shielding materials. As a result, at 100 keV, lead shielding showed the least amount of transmitted dose compared to other shielding materials. However, lead shielding also showed the highest reflected dose at the same incident photon energy. As copper showed the least amount of reflected dose at this incident energy, hence applying a thin layer of this material to lead shielding can tolerate the compromise between low transmitted dose and high reflected dose. Therefore, this can improve the radiation shielding at various irradiation facilities. In conclusion, the reflected dose for all materials studied will increase or higher when the incident photon energy increase, except for lead as well as for low-Z element materials rather than high-Z element materials.

For an X-ray room, there is a special window for radiation workers to monitor the patient during an irradiation procedure. Lead glass commonly used as protective window materials for diagnostic X-rays even it is known for its toxicity due to the lead oxide in the air which could be inhaled either during manufacturing or recycled process. Monte Carlo simulation (EGS5 code) was used to study several other types of available protective windows for its radiation shielding efficiency. In this study, the practicability of acrylic glass, plate glass and Pyrex glass systems with respect to lead glass were studied for protective window materials. The photon attenuation coefficients (μ), the percentage of transmitted and reflected photon energy spectra and half-value layer (HVL) were investigated by using simulation. Three photon source energies of 59.5 keV, 150 keV, and X-ray 150 kVp were calculated via EGS5 code to study the capability of these four glass systems as low energy photons radiation shielding materials. A thickness of 7 cm plate glass, 8 cm pyrex glass and more than 10 cm acrylic glass are adequate as a non-lead shielding material for 150 kVp X-ray to have a similar lead-glass equivalency. The use of plate glass as radiation protecting material to replace lead glass can reduce expenses as plate is way cheaper than lead but the increase thickness of plate will need special framing and concerns of its increased weight needs to be considered. However, given that the X-ray primary beam will not be directed towards the protective windows, therefore the findings are appropriate, with less thickness of plate glass could be used.