So how is all of this extensive advice and guidance supposed to be implemented and actually applied to different radiation exposure situations? It goes without saying that the detailed interpretation can be complex indeed, but by and large it all follows much the same pattern, which can be summarized as follows:

(i) A characterisation of the possible situations where radiation exposure may occur (planned, emergency and existing exposure situations).

(ii) A classification of the types of exposure (those that are certain to occur and potential exposures, as well as occupational exposure, medical exposure of patients and public exposure).

(iii) An identification of the exposed individuals (workers, patients and members of the public).

(iv) A categorisation of the types of assessment, namely source-related and individual-related.

(v) A precise formulation of the principles of protection: justification, optimisation of protection, and the application of dose limits.

(vi) A description of the levels of individual doses that require protective action or assessment (dose limits, dose constraints and reference levels).

(vii) A delineation of the conditions for the safety of radiation sources, including their security and the requirements for emergency pre­paredness and response.

Radiological protection is undertaken within the UK under various pieces of legislation, including a number of regulations, the developments of which have been recorded in some detail by O’Riordan.19