[en] In physical science the absorbed dose represents a specific quantity. By definition, absorbed dose is the energy imparted by ionizing radiation to matter in a volume element. The absorbed dose may change in the body from one point to another. This depends on the atomic composition and density of matter interacting with radiation at various locations. This specific quantity is particularly suitable for a quantitative description of spatial dose distributions. For risk assessment the absorbed dose or dose equivalent is used as a reference quantity. However, for the risk evaluation itself more integral quantities, e.g. volume dose or area exposure product seem to be more appropriate. (orig.)