[An improved method to stimulate water and biological tissues in relation to linear interactions with photons and fast electrons (author's transl)]

Radiation physical problems in clinical dosimetry often need for their experimental solution the linear coefficients of interaction between radiation and irradited matter. Using modified material parameters (the products of mass density and the earlier defined effective material parameters) it was possible to derive an improved method to calculate the composition of an equivalent for a material to be substituted. The method is described and its usefulness demonstrated by some examples. A geometric analogue facilitates the solution if a computer is not available. Some comparisons are made between this method and the basic data method of White.