Application of dose limits for protection of patients
Medical exposures of patients have been properly justified and that the associated doses are commensurate with the medical purpose, so it is not appropriate to apply dose limits or dose constraints to the medical exposure of patients; such limits or constraints would often do more harm than good (ICRP Publication 105 Radiological Protection in Medicine). Often, there are concurrent chronic, severe, or even life-threatening medical conditions that are more critical than the radiation exposure itself. The emphasis is then on justification of the medical procedures and on the optimisation of radiological protection (ICRP Supporting Guidance 2 Radiation and your patient - A Guide for Medical Practitioners).
In most situations in healthcare, other than radiation therapy, it is not necessary to approach the thresholds for tissue reactions, even for the most part in fluoroscopically guided interventional procedures, if the staff are properly educated and trained. The Commission’s policy is therefore to limit exposures so as to keep doses below these thresholds. The possibility of stochastic effects cannot be eliminated totally, so the policy is to avoid unnecessary sources of exposure and to take all reasonable steps to reduce the doses from those sources of exposure that are necessary or cannot be avoided.