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The concept of radiation shielding is well known in modern day to day applications including nuclear reactors to sunblock cream used for human beings. Consider the following image as first lesson on understanding the concept of radiation shielding: Let's try to understand radiation shielding effectiveness by a simple example. Let's consider a thin plate receiving radiations on one side from a radiation source at 650C and radiates on the other face to a surface at 150C. As a first step, determine the temperature of thin plate. For simple analysis, consider emissivity =1 and neglect convection heat flow. In second step, according to your observation, is thin plat an effective radiation shielding material based on information above