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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Which of these is not a basic principle of radiation protection ?
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The correct answer is  In addition to the three basic principles of radiation protection (justification, limitation, and optimization), one  can apply the following additional techniques to reduce the radiation burden to the patient:

Collimation of the x-ray beam.
Correct focus-to-skin distance.
Lead apron with thyroid collar.
More radiation-sensitive image receptors.