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01. Introduction
In this era medical imaging modalities become more advanced among medical areas like plain radiography, fluoroscopy, computed tomography, and dental radiography etc. radiation is the most powerful tool that used in medical imaging to diagnose purposes (Arkadiusz Szarmach et al., 2015). Radiation can be categorized into two approaches; they are ionizing radiation and nonionizing radiation. The use of ionizing radiations for the diagnose diseases and make decisions based on these imaging modalities. According that usage of ionizing radiation, those who deal with radiation hazard must be aware of these imaging modalities and concern of radiation protection. Radiation can also directly ionize or damage DNA and other biologic molecules: RNA, proteins, lipids. ( Colosi & ColosI, 2011).