Part 1 presents a systematic outline of the current theory of radiation risk. The most basic ideas of the theory can be expressed by two quantities which represent the administrative approach to radiation risk. These quantities are “specific dose”, D8, which relates to individual organs or tissues and “overall dose”, D0, which relates to the entire human body. By taking D8 and D0 as a starting point and by using postulational methods, two auxiliary quantities have been derived which are “dose equivalent”, De(r), and quality factor, Q. Dose equivalent, De(r), is a macroscopic field quantity and is, therefore, different from the ICRP defined dose equivalent, H, which is microscopic. In Part 2 an experimental program and a computational program are outlined for obtaining a relationship between Q and linear energy transfer, L. It is shown that by applying Monte Carlo procedures one can determine distributions of L in critical organs of animals exposed to ionizing radiations. Then, using biological data for critical effects (extrapolated from high radiation levels to presumed effects at low levels), sets of linear equations can be obtained in which the coefficients are the doses delivered in intervals of L, and the unknowns are “biological weighting factors”, a. From these equations one can derive lambda's for various L's as they relate to critical effects in animals. Then, using value judgment and combining the calculated results with data observed on men, one can obtain a Q-L relationship which is more directly based on experimental evidence than that which is currently used.
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