The ICRP, in its most recent recommendations (ICRP, 2007), has updated its system of radiological protection. However, the changes in relation to its previous recommendations (ICRP, 1991) are comparatively minor and for the most part are concerned with clarifying the previous recommendations (Wrixon, 2008).

The central assumption of a linear dose-response relationship for the induction of cancer and heritable effects, according to which an increment in dose induces a proportional increment in risk even at the lowest doses, continues to provide the basis for the protection system.