Medical exposure. Guidance on the 1990 Recommendations of ICRP

The Board has been directed by the Health Ministers to advise the appropriate government departments and statutory bodies on the acceptability and applicability for the UK of recommendations of the International Commission on Radiological Protection (ICRP). The Board has given its response to the broad issues raised by the new ICRP recommendations and is providing more specific advice on the three categories of exposure considered by ICRP, namely occupational, medical and public, as well as on dose quantities. This document presents advice on medical exposure of patients from diagnostic radiology, nuclear medicine and radiotherapy, and on exposures (other than occupational) incurred by those helping in the support and comfort of such patients. The report contains recommendations concerning the justification of medical exposures both at the broad level of practice and for individual procedures. It discusses the importance of optimisation of protection and, in the context of diagnostic medical exposures, recommends the use of reference dose levels to give a quantitative guide to optimisation. Reference values of entrance surface dose per radiograph and dose-area product per examination are presented for some common types of X-ray procedure. Consideration is given to the suitability of effective dose for assessing detriment from diagnostic medical exposures. Dose constraints are proposed for medical exposures incurred by individuals other than as part of their own medical diagnosis or treatment and some issues regarding public exposure from medical radiology are discussed. (Author)