7. Radiation Protection, Dose Limits and Pregnancy

The reasoning: three ICRP principles

1. Justification: net benefit for this patient and this question (appropriateness criteria, alternative non‑ionising tests).
2. Optimisation: ALARA: protocol choice, collimation, paediatric settings, automatic exposure control, iterative reconstruction, avoiding repeats; diagnostic reference levels (DRLs) benchmark practice.
3. Dose limitation: applies to occupational and public exposure only, never to justified patient exposure.