Estimation of risks from medical irradiation

This paper discuss various concepts of quantifying risks from medical irradiation. The expected individual risk from specific medical examination can be derived by estimation the dose-equivalent in different organs and tissues and apply the risk factors recommended for these tissues. A more practical way is to estimate or measure the energy imparted which has been found to correlate quite well with the total risk derived by summing up the risks for the involved tissues. The effective dose-equivalent concept can be used to derive the collective effective dose-equivalent in a population in order to compare the contribution from medical exposure with the contribution from other sources of irradiation in the society. In many countries it is thus shown that medical exposures gives the largest man-made contribution to the population dose